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  3. The Better-RSI Showdown: We Tested 4 RSI Upgrades on SPY, QQQ, IWM, and DIA

September 10, 2026

The Better-RSI Showdown: We Tested 4 RSI Upgrades on SPY, QQQ, IWM, and DIA

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9 min read

Written by Ali Casey, founder of StatOasis and AlgoChef, creator of the Algo Trading Masterclass (ATM), with over 10 years of experience building systematic trading tools - building algorithmic strategies, testing ideas with data, and teaching traders how to build structured, portfolio-based trading workflows.

Published September 10, 2026 · Method

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Table of contents▾
  • TL;DR
  • Is there a best RSI indicator?
  • How we tested: 1,856 backtests across four ETFs
  • Finding #1: Which families were profitable?
  • Finding #2: Do the upgrades actually beat plain RSI?
  • Finding #3: High win rate, negative returns — the trap
  • Finding #4: Which family draws down the least?
  • Finding #5: Does Triple RSI really achieve a 90% win rate?
  • The head-to-head: best variant per family
  • The verdict, and the honest caveats
  • Findings at a glance
  • Key takeaways
  • Methodology: how this data was generated
  • Disclaimer
  • Get the next study in your inbox
  • Methodology
  • FAQs

The short version

We ran 1,856 backtests across four RSI families — plain RSI, Connors RSI, Laguerre RSI and Z-Score RSI — on SPY, QQQ, IWM and DIA, plus a separate Triple RSI test. Two of the upgrades beat plain RSI by a modest margin and one is clearly worse: Z-Score RSI posted a median CAR of 1.05% against the plain-RSI baseline's −0.15%, while Laguerre RSI came in at −0.66% with a 66.22% median drawdown. The Triple RSI "~90% win rate" claim did not reproduce — our SPY runs landed between 58.9% and 65.1%.

Methodology & risk note: Backtested event study across SPY, QQQ, IWM, and DIA daily price data, 1,856 strategy variants, frictionless. Results are hypothetical and not investment advice — past patterns don't guarantee future results. Full method and disclaimer below.

TL;DR

  • Two variants actually beat plain RSI. Connors RSI and Z-Score RSI modestly outperform the plain-RSI baseline on median risk-adjusted return across all tested configurations. The edge is real, but it is not dramatic.
  • Laguerre RSI underperforms. Despite its "lag-free" marketing, Laguerre RSI produced the worst median results of the four families: negative median CAR, the lowest share of profitable variants, and the largest median drawdown at 66.2%.
  • The Triple RSI "~90% win rate" doesn't show up here. Actual win rates on our implementation: 56–65% across SPY, QQQ, IWM, and DIA depending on hold period. All configurations were profitable. The ~90% figure, attributed to QuantifiedStrategies, is not reproduced.
  • High win rate doesn't mean profit. Five variants in this study had win rates above 60% and still lost money — all on the short side, where small wins absorbed one large directional loss.

CAR is compound annual return; MaxDD is maximum drawdown, the largest peak-to-trough loss. CAR/MaxDD combines them: a higher number means more return for the drawdown taken.

Is there a best RSI indicator?

Every trading YouTube channel runs the same playbook. An eye-catching title. A win-rate claim in the thumbnail. A "secret" indicator that fixes RSI's problems.

The titles alone make the case: "Stop Using RSI, Use This SECRET Indicator Instead" (StatOasis video #15), "Lag-Free Trading? The Hidden Power of Laguerre RSI" (#10), "Z-Score RSI: The Upgrade You Didn't Know You Needed" (#11). And for the boldest claim: "Triple RSI Trading Strategy: Boost Your Win Rate to 90%" from QuantifiedStrategies, covered in StatOasis video #3.

Trading decisions made on thumbnails have a poor track record. So we ran the backtests.

Four RSI variants, four major US index ETFs, 1,856 strategy configurations, all scored the same way. Two variants hold a real edge over plain RSI. One significantly underperforms. The headlining win-rate claim does not survive an honest test.

The plain-RSI baseline used here comes from our earlier RSI vs Stochastic vs Williams %R study, which tested plain RSI as part of a 33,792-variant oscillator comparison.

How we tested: 1,856 backtests across four ETFs

Here is exactly what sits behind every number below.

  • Instruments: SPY, QQQ, IWM, and DIA — four major US index ETFs.
  • Window: each ETF's full daily history through 2026. SPY runs from February 1993, DIA from January 1998, QQQ from March 1999, and IWM from June 2000.
  • Families tested: plain RSI (1,152 variants), Connors RSI (288 variants), Laguerre RSI (128 variants), Z-Score RSI (288 variants) — 1,856 total. Triple RSI was tested separately as a rule-based signal mini-backtest.
  • What we varied: indicator settings (lengths, thresholds), trade direction (long / short), and a protective time exit (0, 5, 10, or 15 bars — where 0 means the indicator decides the exit).
  • Position rules: $10,000 fixed per position, no compounding, one position at a time.
  • Fills: signals computed on the close and filled at the next open, so there's no look-ahead.
  • Costs: frictionless. No commission, no slippage. The numbers are base rates — you would need to cover real execution costs on top of them.

Indicators defined:

Connors RSI combines three components in equal weight: RSI(3) of price, RSI(2) of the consecutive-day win/loss streak, and a 100-period percent rank of the 1-day rate of change. Developed by Larry Connors. Recommended thresholds are 90/10 rather than plain RSI's 70/30, because the composite moves faster. We use the canonical formula (rsi_len=3, streak_len=2, rank_len=100).

Laguerre RSI applies a 4-pole Laguerre digital filter, developed by John Ehlers in 2004, to price before computing the RSI ratio. A single parameter, gamma, controls the smoothing. Low gamma (e.g., 0.2) gives faster, more sensitive signals; high gamma (e.g., 0.7–0.8) gives slower, smoother ones. Our implementation uses gamma=0.5 and outputs 0–100. The canonical Ehlers formula outputs 0–1; the math is identical, the scale is multiplied by 100. Thresholds are 80/20.

Z-Score RSI (StatOasis formulation): first compute Wilder RSI(14), then re-express each RSI value as a rolling z-score over the past 20 RSI readings (using population standard deviation). A reading of +2 means RSI is 2 standard deviations above its recent average; −2 means 2 below. Output is unbounded and centered at 0. This is a specific formulation worth noting: some platforms use "Z-Score RSI" to mean RSI applied to z-scored prices, which is the reverse approach. The StatOasis version normalizes the RSI output itself, measuring whether RSI is at a historical extreme relative to its own recent behavior rather than whether raw price is statistically stretched.

Triple RSI fires a long-only entry when all three conditions hold at the close: (1) RSI has declined for 3 consecutive bars, (2) RSI is below 30, (3) price is above SMA(200). We tested RSI(2), our default, and RSI(5), the canonical QuantifiedStrategies version.

Finding #1: Which families were profitable?

The share of profitable configurations gives the first read on each family.

FamilyVariantsProfitable% Profitable
RSI (plain)1,15260852.8%
Connors RSI28815553.8%
Laguerre RSI1286450.0%
Z-Score RSI28815553.8%
Every family clusters between 50.0% and 53.8% profitable, so no upgrade meaningfully changes your odds of picking a winning configuration — and Laguerre RSI's 50.0% is a coin flip.

The spread across families is narrow. All four sit between 50% and 54% profitable. No family dominates by a large margin, but Laguerre RSI finishes last. Exactly half its variants lost money — below the plain-RSI rate — which means Laguerre's default parameter space does not reliably produce an edge across this universe.

Connors RSI and Z-Score RSI both land at 53.8%, edging out plain RSI's 52.8%. A small gap, and it shows up in the other metrics too.

Finding #2: Do the upgrades actually beat plain RSI?

Counting profitable variants tells you how many were positive, not how well they performed. Median CAR and median CAR/MaxDD answer that.

FamilyMedian CARBeats RSI?Median CAR/MaxDDBeats RSI?Median NetProfit
RSI (plain)−0.15%—0.000—$940
Connors RSI0.32%YES0.010YES$2,451
Laguerre RSI−0.66%NO−0.010NO$245
Z-Score RSI1.05%YES0.030YES$4,413
The typical Z-Score RSI variant compounded at 1.05% a year against the plain-RSI baseline's −0.15%, while the typical Laguerre RSI variant lost 0.66% a year.

Connors RSI and Z-Score RSI beat the plain-RSI baseline on every measure: higher median CAR, better median CAR/MaxDD, higher median net profit. Z-Score RSI is the bigger mover, with a median CAR of 1.05% versus the baseline's −0.15%.

Laguerre RSI goes the other direction. A median CAR of −0.66%, a negative median CAR/MaxDD, and the lowest median net profit of any family at $245 — roughly 26% of plain RSI's $940. Switching from plain RSI to Laguerre RSI across the full parameter space tested here would have made results worse on every dimension.

The improvements from Connors RSI and Z-Score RSI are real. They are also modest. "Modest but real" is a more accurate description than "secret indicator" or "upgrade you didn't know you needed."

Finding #3: High win rate, negative returns — the trap

Win rate is probably the most misunderstood statistic in trading. A strategy can win 60% of its trades and still lose money if the losses on the remaining 40% are large enough to swamp the gains.

This study produced five examples of exactly that — win rates above 60%, negative net profit.

FamilySymbolSideWinPctNetProfitTrades
RSIIWMLong65.1%−$51843 (small sample)
RSIIWMShort61.6%−$6,539125
RSIIWMShort60.6%−$4,592582
RSIQQQShort60.4%−$2,242639
RSIQQQShort60.1%−$3,603574
Win rate tells you almost nothing about profit: the study's worst loser won 55.1% of its trades and still finished at −$21,637.

Four of the five are on the short side of RSI mean-reversion strategies on index ETFs. US equity index ETFs trend upward over time. A short mean-reversion strategy wins on small countertrend bounces — the market ticks up briefly, the short closes for a gain — then hits one sustained upward move that wipes out many small winners in a single trade.

The worst dollar loss in the study is not even in the 60%+ cluster. It belongs to Laguerre RSI on QQQ Short: a 55.1% win rate paired with a net profit of −$21,637. Win more than half your trades by a clear margin, still end up significantly negative. This is the win-rate trap in its starkest form.

Win rate alone tells you nothing useful. The ratio of average win to average loss — and whether you are trading with or against the structural drift of the instrument — determines the outcome.

The mirror-image trap: perfect win rates on tiny samples

The same data holds the opposite illusion, and it is just as dangerous. The highest win rates in the entire 1,856-variant sweep look spectacular on paper: a plain-RSI configuration on QQQ Long with a 100% win rate, and one on DIA Long at 94.1%. Sort the sweep by win rate and the top of the leaderboard reads like a holy grail.

Then read the trade counts. The 100% variant won 5 trades out of 5 — total profit $1,900. The 94.1% variant won 16 of 17. Every single one of the ten highest-win-rate variants in the study sits below 50 trades, which is exactly why the engine flags anything under that threshold as statistically unreliable rather than celebrating it. Five coin flips landing heads is not a biased coin.

So the win-rate statistic fails in both directions: a 60% win rate can lose $6,500 (the short-side trap above), and a 100% win rate can be five lucky trades. The two numbers that rescue it are the ones this study leans on everywhere — the trade count, and the win/loss size ratio behind the rate.

Finding #4: Which family draws down the least?

Risk matters as much as return. A strategy with a 90% drawdown is not tradeable for most people regardless of its return figure.

FamilyMedian MaxDDPct
Connors RSI35.92%
Z-Score RSI38.27%
RSI (plain)40.65%
Laguerre RSI66.22%
The typical Laguerre RSI variant gave back 66.22% peak-to-trough, nearly double Connors RSI's 35.92% — a hole most accounts never sit through.

Connors RSI and Z-Score RSI carry lower median drawdowns than plain RSI. At 35.92% and 38.27% against plain RSI's 40.65%, the drawdown numbers line up with the return picture from Finding #2. The same two families win on both dimensions.

Laguerre RSI's 66.22% median drawdown is in a different category. Most traders cannot hold through a two-thirds peak-to-trough loss in a real account. The best individual Laguerre RSI variant — QQQ Long, thresholds 20/80, 5-bar exit — had a 20.86% drawdown on 355 trades and net profit of $28,961. But that is the top of the distribution, not the typical result. At the median, Laguerre RSI draws down roughly 66%.

Finding #5: Does Triple RSI really achieve a 90% win rate?

This is the claim that drew the most scrutiny. QuantifiedStrategies describes Triple RSI as achieving a "90–91% win rate" on SPY since 1993. StatOasis video #3 covers the strategy and common implementation pitfalls.

We tested two versions: RSI(2), our implementation, and RSI(5), the canonical QuantifiedStrategies version. Both used the 3-condition rule described in "How we tested" above. Neither included the "RSI below its value 63 bars ago" volatility filter that appears in the original canonical version.

RSI(2) on SPY — 5-bar hold: 445 trades, 59.1% win rate, $13,844 net profit. RSI(2) on SPY — 10-bar hold: 332 trades, 65.1% win rate, $22,791 net profit. RSI(5) on SPY — 5-bar hold: 185 trades, 58.9% win rate, $7,546 net profit. RSI(5) on SPY — 10-bar hold: 155 trades, 64.5% win rate, $11,541 net profit.

The claimed rate is not close. Our best SPY configuration won 65.1% of its trades — profitable, but well short of the ~90% headline.

Neither version reproduces a 90% win rate. Win rates of 59–65% on SPY are real and positive — every SPY configuration produced a profit — but 65% and 90% are not close.

Two factors likely explain the gap. First, the canonical version includes a "RSI below its 63-bar-ago value" condition that filters out lower-quality signals during certain market regimes. Removing that filter lets through trades the original version would skip, which pulls the win rate down. Second, the canonical study reports 78 trades on SPY since 1993; our RSI(5) version generates 185 trades over the same period. More signals under the same 3-condition rule means the signal is firing at lower-conviction moments. A tighter filter that takes fewer trades can achieve a higher win rate precisely because it discards the borderline cases.

All tested configurations were profitable. The ~90% win rate is not what a straightforward implementation of the publicly available rules produces.

Across all four ETFs at the 5-bar hold, the RSI(2) aggregate was 1,482 trades at a 56.3% weighted win rate and $36,235 combined net profit. At the 10-bar hold, 1,099 trades at 60.6% and $55,851. Every configuration was profitable. None reached 90%.

The head-to-head: best variant per family

Here is the best reliable variant (minimum 50 trades) from each family, ranked by CAR/MaxDD.

FamilyBest variant settingsCAR/MaxDDWinPctNetProfitTrades
Connors RSIQQQ Long, length 3, lower 10, upper 70, 5-bar exit1.25077.5%$17,863111
Z-Score RSIQQQ Long, length 14, lower −2.0, upper 1.0, 5-bar exit1.17064.8%$19,348182
RSI (plain)QQQ Long, length 2, lower 5, upper 75, no time exit1.11076.7%$30,485180
Laguerre RSIQQQ Long, lower 20, upper 80, 5-bar exit0.46060.9%$28,961355

At their best, all four families find profitable configurations. Connors RSI and Z-Score RSI edge out plain RSI at the top. Laguerre RSI's best variant trails considerably on risk-adjusted performance even with the highest trade count in the group.

Treat these figures as upper-bound illustrations, not representative expectations. The median results in Findings #2 and #4 are a more honest picture of what a typical parameter choice delivers.

The verdict, and the honest caveats

Two of the four tested RSI upgrades outperform plain RSI in this 1,856-variant test. Connors RSI and Z-Score RSI beat the plain-RSI baseline on median CAR, median CAR/MaxDD, and share of profitable variants. The advantage holds across all three measures but is not large on any of them.

Laguerre RSI underperforms plain RSI on every measured dimension: negative median CAR (−0.66% vs −0.15% for plain RSI), negative median CAR/MaxDD, the lowest profitable-variant rate (50.0%), and the largest drawdowns. The "lag-free" framing is a marketing claim; the backtested performance here does not support it.

The Triple RSI "~90% win rate" claim, attributed to QuantifiedStrategies, does not hold under our implementation. Actual results run 59–65% on SPY and 56–61% on the four-ETF aggregate. Those are positive, profitable win rates. They are not 90%.

Now the limits, because a study that hides them isn't worth trusting.

  • Frictionless. Every number was computed with no commission and no slippage. Real costs would shrink any edge, and the thin ones might not survive. Read these magnitudes as relative, not as take-home returns.
  • An event study, not a deployable system. This measures base rates across configurations. It tells you where edges concentrate, not how to build a risk-managed strategy. That is separate work.
  • The Triple RSI comparison is not exact. The canonical QuantifiedStrategies version includes a "RSI below its 63-bar-ago value" filter that our implementation does not have. Results are not directly comparable to the original claim.
  • Best-variant numbers are cherry-picked optima. The top strategies in each family are the top of their distribution. The median results are the more honest benchmark.
  • Laguerre RSI sweeps only gamma=0.5. Different gamma values would produce different results. This is a single-parameter-value test for this family.

Findings at a glance

FindingThe numberWhat it means
Connors RSI beats RSIMedian CAR 0.32% vs −0.15%Consistent, modest improvement on risk-adjusted return
Z-Score RSI beats RSIMedian CAR 1.05% vs −0.15%Largest improvement of the four families
Laguerre RSI underperformsMedian CAR −0.66%, median MaxDD 66.2%Worse than plain RSI on every measure
Win-rate trap5 variants: 60%+ win rate, negative net profitShort-side RSI on IWM/QQQ; win rate alone is misleading
Triple RSI actual win rate56–65% across 4 ETFs (not ~90%)Profitable on all configs, but the canonical claim is not reproduced
Best Connors variantCAR/MaxDD 1.250, 77.5% win rate, $17,863QQQ Long, thresholds 10/70, 5-bar exit, 111 trades
Best Z-Score RSI variantCAR/MaxDD 1.170, 64.8% win rate, $19,348QQQ Long, z-score thresholds −2.0/1.0, 5-bar exit, 182 trades

Key takeaways

  • Two upgrades hold up, one doesn't. Connors RSI and Z-Score RSI modestly outperform plain RSI on median risk-adjusted return across 1,856 variants. Laguerre RSI underperforms on every tested dimension.
  • The win-rate trap is real on the short side. Strategies with 60%+ win rates that end up losing money are not a hypothetical — five exist in this data, all tied to short mean-reversion strategies on upward-trending index ETFs.
  • The canonical Triple RSI win rate is not reproduced. Win rates of 59–65% on SPY are genuine and the strategy is profitable. The ~90% figure requires conditions beyond our implementation, specifically the 63-bar-ago RSI filter.
  • Laguerre RSI carries the largest drawdowns in the study. A median MaxDD of 66.22% makes the typical configuration difficult to hold in a real account regardless of win rate.
  • Best-variant performance is real but not typical. The top Connors RSI variant hit a CAR/MaxDD of 1.250. The median Connors RSI variant hit 0.010. The gap between "best" and "typical" is wide in every family.

Methodology: how this data was generated

This is a backtested event study, not live trading results. The numbers come from our in-house research engine run over the full daily price history of each ETF.

  • Data source: Daily OHLCV (open, high, low, close, volume) price data for SPY, QQQ, IWM, and DIA.
  • Date range: SPY from February 1993, DIA from January 1998, QQQ from March 1999, IWM from June 2000, all through June 2026.
  • Variants: 1,856 total across four RSI families (RSI 1,152, Connors RSI 288, Z-Score RSI 288, Laguerre RSI 128), sweeping indicator settings, direction (long / short), and time exit (0 / 5 / 10 / 15 bars). Triple RSI tested separately as a rule-based mini-backtest.
  • Entry and exit: signals computed on the close and filled at the next open (no look-ahead). One position at a time, $10,000 fixed per position, no compounding.
  • Reliability threshold: 50 trades minimum. Variants below this are flagged, not dropped.
  • Scoring: each variant measured for percent profitable, median and best net profit, win rate, CAR, MaxDDPct, and CAR/MaxDD.
  • Frictionless assumption: computed without commissions or slippage. Real-world costs would reduce any edge shown here.

Disclaimer

All results in this article are derived from historical backtesting using daily ETF price data and do not represent actual trading results. Backtested performance is hypothetical. Past performance of any pattern does not guarantee future results. This article is for educational and informational purposes only and does not constitute investment advice. StatOasis is not a registered investment advisor. Nothing here is a recommendation to buy or sell any security. Please consult a licensed financial professional before making any investment decision.

Transparency: StatOasis sells trading-education products. Our research is produced independently and is not altered to favor a sale.

Freshness: The data is current through June 2026. We re-review these studies when the underlying datasets are extended.

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This is one study in an ongoing series. If you want the next one — the same kind of head-to-head, myth-busting, frictionless-but-honest backtest — join The Overfit newsletter at StatOasis.com/Overfit. It's where we publish the data behind the trading ideas everyone argues about.

Which RSI you pick matters less than which win rate you refuse to trust.

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Methodology

Data source
Daily OHLCV (open, high, low, close, volume) price data for SPY, QQQ, IWM and DIA, from the StatOasis in-house research engine.
Date range
SPY from February 1993, DIA from January 1998, QQQ from March 1999, IWM from June 2000 — all through June 2026.
Entry / exit rules
1,856 variants across four RSI families (RSI 1,152, Connors RSI 288, Z-Score RSI 288, Laguerre RSI 128), sweeping indicator settings, direction (long/short) and time exit (0/5/10/15 bars). Signals are computed on the close and filled at the next open — no look-ahead. Triple RSI is tested separately as a rule-based mini-backtest. Each variant is measured for percent profitable, median and best net profit, win rate, CAR, MaxDDPct and CAR/MaxDD.
Sizing
$10,000 fixed per position, one position at a time, no compounding. Frictionless: no commission or slippage.
Overlap mode
Flat-only — one position at a time, so overlapping signals are skipped. Reliability floor of 50 trades; variants below it are flagged, not dropped.
Look-ahead
Every RSI variant is computed on the close of bar t and filled at the open of bar t+1, entries and exits alike. No number depends on information unavailable at the decision.
Minimum sample
50 trades. 1,719 of the 1,856 variants clear it; thinner cells are flagged, never dropped.
Buy-and-hold benchmark
Buy and hold each market over the same window on the study's own $10,000 basis: SPY $157,639.52 net at 8.82% CAGR (worst drawdown 56.47%), QQQ $130,615.64 at 10.17% (83.32%), IWM $48,782.44 at 7.05% (59.46%), DIA $56,814.18 at 6.91% (53.80%).
Random control
Frequency-matched seeded coin flip per market, 10 seeds from base seed 20260803, matched to each market's own median reliable variant (SPY 366 entries / 9-bar hold, QQQ 304/9, IWM 287/9, DIA 293/9). Net: SPY $8,398.12 (sd $3,664.85), QQQ $5,775.16 (sd $6,334.83), IWM $6,397.87 (sd $5,173.73), DIA $8,247.10 (sd $3,939.41). Computed by tools/controls_report.py.
Parameter scopeParameters swept

The study searched the parameter space and reports the spread, not one tuned setting.

1,856 variants across four RSI families (RSI 1,152, Connors RSI 288, Z-Score RSI 288, Laguerre RSI 128), sweeping indicator settings, direction and time exits of 0/5/10/15 bars on four ETFs. The article reports the spread across that space rather than one tuned upgrade.

Run to v1 of the StatOasis research standard - the rules every study here has to meet before it is published. The version is the study's own: a standard that gained a rule later never reaches back and claims this one met it.

Historical backtest results are not a guarantee of future returns. This content is for educational purposes only and is not investment advice. Hypothetical performance disclosure (CFTC Rule 4.41).

Frequently asked questions

What is Connors RSI and how does it differ from plain RSI?⌄

Connors RSI is a composite oscillator that averages three components: RSI(3) of price, RSI(2) of the consecutive-day win/loss streak, and the 100-period percent rank of the 1-day rate of change. It moves faster than plain Wilder RSI, which uses only the ratio of average gains to average losses. Because it compounds multiple signals into one reading, Connors RSI applies more extreme thresholds of 90/10 rather than the standard 70/30.

What is Laguerre RSI and what does the gamma parameter control?⌄

Laguerre RSI, developed by John Ehlers in 2004, applies a 4-pole Laguerre digital filter to price before computing the RSI ratio. The gamma parameter controls smoothing: a lower gamma (e.g., 0.2) produces faster and more sensitive signals; a higher gamma (e.g., 0.7–0.8) produces slower and smoother ones. The default balanced value is 0.5. In this test using gamma=0.5, Laguerre RSI produced the worst median performance of the four families: median CAR of −0.66% and median maximum drawdown of 66.22%.

What is Z-Score RSI — how does normalizing RSI by z-score change how you read it?⌄

Z-Score RSI (StatOasis formulation) takes Wilder RSI(14) and re-expresses each reading as a rolling z-score over the past 20 RSI values (using population standard deviation). Instead of asking "is RSI above 70?", it asks "is RSI unusually high relative to where it has been recently?" A z-score of −2 means the current RSI reading is 2 standard deviations below its recent average, which represents a stronger oversold signal in a prolonged downtrend than a fixed 30-level threshold would. Note that some platforms use the "Z-Score RSI" label for a different formulation — applying RSI to z-scored prices. The StatOasis version normalizes the RSI output itself.

What is the Triple RSI strategy and what are its exact entry rules?⌄

Triple RSI fires a long entry when all three conditions hold at the close: RSI has declined for 3 consecutive bars, RSI is below 30, and the closing price is above SMA(200). Exit is a fixed hold period. The canonical QuantifiedStrategies version adds a fourth condition — RSI below its value 63 bars ago — which acts as a volatility and regime filter. That condition is not included in our implementation, which likely explains much of the gap between the claimed and measured win rates.

Does Triple RSI really achieve a 90% win rate?⌄

Not in our test. The ~90% win rate (from QuantifiedStrategies, for RSI(5) on SPY since 1993) was not reproduced. Our RSI(2) on SPY produced a 59.1% win rate at 5-bar hold and 65.1% at 10-bar hold. Our RSI(5) on SPY produced 58.9% and 64.5% at those same holds. All configurations were profitable, but the gap between 65% and 90% is substantial. The missing 63-bar-ago RSI filter is the most likely explanation, along with differences in which signals are counted.

Which RSI variant has the highest win rate on SPY?⌄

In the Triple RSI mini-backtest, RSI(2) on SPY at a 10-bar hold produced a 65.1% win rate over 332 trades. In the main 1,856-variant sweep, the plain RSI best variant on QQQ Long produced 76.7% over 180 trades, and Connors RSI's best variant achieved 77.5% on QQQ Long over 111 trades. These are the peaks of each distribution, not typical results.

Do these RSI upgrades work on QQQ, IWM, and DIA — or just SPY?⌄

Results vary by ETF but are not limited to SPY. The best reliable variants for both Connors RSI and Z-Score RSI came from QQQ, not SPY. The Triple RSI aggregate across all four ETFs was profitable on every symbol, though DIA showed the weakest performance with a 1.13% CAR at the RSI(2) 5-bar hold. QQQ was consistently the strongest performer across family-level comparisons.

Does Connors RSI still work in 2025?⌄

The data here covers SPY, QQQ, IWM, and DIA through June 2026 and shows Connors RSI at 53.8% profitable variants, positive median CAR of 0.32%, and positive median CAR/MaxDD of 0.010 — all above the plain-RSI baseline. The best reliable variant (QQQ Long, lower 10, upper 70, 5-bar exit) delivered a CAR/MaxDD of 1.250 over 111 trades across a data window that includes the recent period. The edge appears intact, with the standard caveat that frictionless results overstate real-world returns.

What is the best RSI indicator for ETF swing trading?⌄

Based on this study, Z-Score RSI showed the highest median CAR (1.05%) and Connors RSI showed the lowest median drawdown (35.92%) among families that outperformed plain RSI. What is consistent across all four families is that long-side configurations on US index ETFs outperformed short-side by a wide margin. Direction matters more than the specific indicator.

Should I use RSI(2) or RSI(14) — or something else entirely?⌄

RSI(2) is more sensitive and generates far more signals — the RSI(2) Triple RSI version produced 445 trades on SPY versus 185 for RSI(5). The best plain-RSI variant in this study used RSI(2) on QQQ Long (76.7% win rate, 180 trades, CAR/MaxDD 1.110). Z-Score RSI uses RSI(14) as its base before z-score normalization, with the z-score layer providing dynamic sensitivity. The choice depends on desired trade frequency and how much noise you can tolerate in individual signals.

Why does RSI fail in trending markets, and how do the variants handle this?⌄

Standard RSI mean-reversion strategies fire oversold signals during strong downtrends, entering against momentum that may continue. Z-Score RSI partially addresses this by measuring RSI against its own recent history — in a persistent downtrend where RSI stays low, the z-score threshold adjusts, so only a reading that is extreme relative to that depressed RSI level triggers a signal. Connors RSI adds a streak component that reflects the intensity of a directional run rather than just the level. Neither eliminates the trend-trading risk, but both provide a more context-sensitive read than a fixed-level threshold.

Does RSI still work, or has the edge decayed?⌄

The plain-RSI baseline in this study (1,152 variants through June 2026) shows 52.8% profitable and a median CAR of −0.15%. The median variant barely earns its keep. The best configurations are highly profitable — CAR/MaxDD 1.110 at the top. The long mean-reversion edge on US index ETFs appears intact across a 30-plus-year data window. The challenge is not that RSI is broken; it is that the parameter space contains many losing configurations alongside the winning ones, and the median metric makes that visible.

Can a backtested strategy really have a 100% win rate?⌄

Yes — and it means almost nothing. The highest-win-rate variant in this study's 1,856-variant sweep won 100% of its trades: 5 of 5, on QQQ Long, for $1,900 total. All ten of the highest-win-rate configurations in the sweep had fewer than 50 trades, which is the study's reliability threshold. A tiny sample can produce a perfect record by luck alone, which is why trade count is reported next to every win rate here and why sub-50-trade results are flagged rather than trusted.

Which of the four ETFs was hardest for RSI mean reversion?⌄

DIA was consistently the weakest of the four. In the Triple RSI mini-backtest, DIA produced the lowest CAR of any symbol at both holds (1.13% at the 5-bar hold, 1.11% at 10 bars), and no DIA variant appears among the best-per-family picks — all four best reliable variants came from QQQ. IWM was the trap capital of the study on the short side: three of the five 60%+-win-rate money-losers were IWM shorts, including one that lost $6,539 across 125 trades. QQQ was the strongest symbol family-by-family, on both best variants and aggregates.

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Table of contents

  • TL;DR
  • Is there a best RSI indicator?
  • How we tested: 1,856 backtests across four ETFs
  • Finding #1: Which families were profitable?
  • Finding #2: Do the upgrades actually beat plain RSI?
  • Finding #3: High win rate, negative returns — the trap
  • Finding #4: Which family draws down the least?
  • Finding #5: Does Triple RSI really achieve a 90% win rate?
  • The head-to-head: best variant per family
  • The verdict, and the honest caveats
  • Findings at a glance
  • Key takeaways
  • Methodology: how this data was generated
  • Disclaimer
  • Get the next study in your inbox
  • Methodology
  • FAQs

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StatOasis is calm, evidence-based algorithmic-trading education, founded by Ali Casey. Ali builds systematic trading strategies and teaches the workflow behind them: research, build, test, combine, deploy. He writes the Overfit newsletter, published since 2024, and runs the Algo Trading Masterclass.

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