Free crypto futures calculators

Why these two, and not forty

Most trading-calculator pages are lead magnets: forty inputs, a leverage widget, a liquidation-price field, and no reason to believe any of it changed how the next trade was taken. These two exist because they map onto the only two failure modes that show up in almost every blown crypto futures account — the size was wrong before the trade started, or the trade should not have been taken at all.

Everything else is downstream of those. Leverage does not set your risk; position size does, which is why a leverage calculator answers the wrong question. And no amount of strategy work survives the four minutes after a loss if nothing intervenes there.

How to use them properly

• Size before you enter, not after. The position size calculator takes capital, risk percentage, entry and stop, and returns the exact contract size, the margin required and how many consecutive losses would end the account. Run it while the setup is still a plan. Run it after and it is just arithmetic about a decision you have already made.
• Estimate the tilt cost, then measure it. The revenge trading calculator gives you a monthly figure from five numbers you already know. It is an estimate, and estimates about your own behaviour are generous. The real number comes from your fills — which is what the journal is for.
• Nothing here needs an account. Both run in your browser. No signup, no email, no card, and nothing is sent anywhere.

Then run it on your real trades

A calculator tells you what a habit costs in the abstract. Your trade history tells you what it cost you, last month, in money. Connect a read-only exchange key and Postmortem measures the same things from your actual fills — the trades taken minutes after a loss, the ones sized several times your normal, the total drag with a figure on it. The free plan covers one exchange and your last 30 days, with no card.

Further reading: how to size a futures position by risk and how to stop revenge trading.