A good week feels like skill and a bad week feels like a fluke, but the only way to know is to test it. This calculator treats each of your trades as a coin flip weighted by the price you paid, the market's implied probability, and measures how far your actual results land from that baseline.
Enter your record and you'll get an edge in percentage points, a significance score (z), and a plain verdict: real edge, real leak, promising, or just variance. It's the fastest way to answer the question every serious trader asks.
This treats each trade as a coin flip weighted by the price you paid, the market's implied probability, then measures how far your actual wins land from that baseline. It's a quick estimate using one average price; for the real thing, broken down by price band with your own data, run the Edge Lab.
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If you buy contracts at an average price of 50 cents, the market expects you to win about half of them. Win a lot more than that across enough trades and it becomes statistically unlikely to be luck. The calculator computes the expected wins from your average price, compares your actual wins, and expresses the gap as a z-score.
A z of about 2 or more (roughly a 5 percent chance of happening by luck) is the usual bar for calling an edge real. Below that, the honest answer is that you can't yet distinguish your results from chance, no matter how good they feel.
The single biggest mistake traders make is trusting a small sample. Thirty trades tell you almost nothing; the swings from pure luck are enormous. Around a hundred trades the signal starts to firm up, and by several hundred a real edge becomes hard to hide. If the tool says your sample is too small, that's not a dodge, it's the truth.
The flip side: a real leak also needs a sample to prove. If the calculator flags a significant leak, it's worth taking seriously, because that pattern survived the same test your wins would have to.