Every trader wants to know how long before their results actually mean something. The answer depends on two things: how big your edge is, and how much variance your prices carry. This calculator turns that into a concrete number of trades.
The uncomfortable truth it reveals is that small edges take a very long time to prove, and prices near 50 cents (the highest-variance zone) take the longest. A hot week or even a hot month usually isn't enough trades to distinguish skill from luck.
Confidence level
Trades needed
385
to prove a 5-pt edge
At ~5 trades/day
77 days
Smaller edges and prices near 50¢ (highest variance) take far more trades to prove; a big edge or a lopsided price needs fewer. This is why a great-looking month rarely means much. Once you have the trades, test your actual record with the edge significance calculator.
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Why smaller edges take so many trades
Variance scales with the square root of your sample, but the edge you're trying to detect grows linearly. That means halving your edge roughly quadruples the trades you need. A 10-point edge might be provable in around a hundred trades; a 3-point edge can take over a thousand.
Prices matter too. A market priced near 50 cents carries the most variance, so it takes more trades to prove an edge there than at a lopsided price like 15 or 85 cents.
How to use the number
Treat it as a reality check, not a target. If the calculator says you need 400 trades to prove your edge and you have 60, the honest conclusion is that you don't yet know whether you're good, no matter how the results feel. Keep a clean record and keep going.
Once you're in range, run your actual trades through the edge significance calculator or the full Edge Lab to see whether the edge held up. Proving it and having it are two different things, and the sample size is what lets you tell.
FAQ
How many trades do I need to prove a trading edge?
It depends on your edge and prices. A large 10-point edge can be provable in roughly a hundred trades, while a small 3-point edge can take over a thousand. Prices near 50 cents carry the most variance and need the largest samples.
Why doesn't a winning month prove I'm good?
A month is usually too few trades to separate skill from luck, especially for a modest edge. Variance produces winning and losing streaks even with no real edge, so short samples simply can't confirm one.
Does the price I trade at change how many trades I need?
Yes. Markets priced near 50 cents have the highest variance, so proving an edge there takes more trades. Lopsided prices like 15 or 85 cents carry less variance and need fewer.
How is the number calculated?
It comes from the same significance test used to judge a win record: the trades needed for your expected edge to clear the chosen confidence threshold, given the variance implied by your average price.
Stop calculating one trade at a time
ContractTax does this across your whole Kalshi history: real P&L, a Sharp Score that rates your edge, and your tax numbers under every treatment.
These tools are for education and estimation only, not financial or tax advice. Fee estimates use Kalshi’s standard formula and may differ from your actual fees.
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