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Three checks.
No upload.

Every tool here runs in your browser. Nothing is sent to a server, nothing is stored, and there is no account to create. Two of them are checks the BuildIT certifier runs, cut down to a single question; the third models a prop-firm rulebook.

Verdict01

Backtest Lie Detector

Paste a prediction CSV. Get recomputed accuracy, two dumb baselines, five walk-forward folds, a Wilson interval, and a verdict with an exit code.

  • Catches leakage, overfitting, and a model that cannot beat always-bullish.
  • Input date,prediction,actual with 0/1 values.
  • Time under a second on 600 rows.

Run the Lie Detector

Sample size02

How many trades is enough?

Enter a win rate and the number of trades behind it. See the Wilson 95% interval, and how many trades you would need before the interval clears a coin flip.

  • Answers whether 14 wins from 20 means anything.
  • Shows the exact trade count that would make the result evidence.
  • Works for win rates, hit rates, or any pass/fail series.

Open the calculator

Prop firm03

Will the drawdown rule end it?

Simulate your strategy against a prop-firm challenge: profit target, daily drawdown, maximum drawdown, risk per trade and win rate. Get the pass rate over 20,000 runs.

  • Models intraday peaks against the daily cap, the way FTMO does.
  • Reports the failure reason that ends most challenges.
  • Runs a Monte Carlo, not a single lucky path.

Open the simulator

Selection04

Is that Sharpe the best of many tries?

Enter a Sharpe, how long it was measured, and how many strategy variations you tried. Get the probability the true Sharpe is above zero, and the years of data it would take to reach 95% confidence.

  • Deflates the Sharpe by the number of attempts behind it.
  • Reports the minimum track record length at 95%.
  • Copies a one-line summary you can paste into a thread.

Open the check

Why these four, and not a hundred

A backtest can fail in many ways, but almost every failure a buyer actually meets reduces to one of four questions. Did the file beat something dumb? Is there enough data behind the number? Would the strategy survive the account rules it will trade under? And was this the best of many attempts?

The Lie Detector answers the first. The sample-size calculator answers the second. The prop-firm simulator answers the third. The Sharpe check answers the fourth. Everything else — calibration, regime stability, execution friction — needs the full harness, and the full harness needs your data.

If you want the reasoning behind each check, the essays cover it in order: why most backtests lie, why a 70% win rate over 20 trades means nothing, and the math behind prop-firm failure.

What the tools will not tell you

A passing verdict is not a promise of profit. These tools recompute what a file claims and test it against statistics. They do not know your costs, your broker, your slippage, or the next market regime. A strategy can clear every check here and still lose money live — that is why the checks exist, not a reason to skip them.

Nothing here is investment advice. The tools are educational, and past backtest results do not predict future returns.