Free · no sign-up · no tips, no picks
The maths of the exchange.
Done honestly.
Six calculators for people who bet or trade on betting exchanges — hedging, lay liability, dutching, commission, the Expert Fee, odds conversion. They compute; they don't predict.
The tools
Six calculators. Zero promises.
Why this site exists
Most betting maths sites want to sell you a system. We want to sell you arithmetic.
Openly: this site is run by Sports Trading OS, which publishes a £47 manual teaching exchange trading as probability management — order-flow skills, hard risk discipline, losses treated as normal. The calculators are free either way, and none of them will tell you what to bet on. Nothing does that honestly.
Straight answers
Are these calculators free?
Yes — free, unrestricted and no sign-up. They run entirely in your browser; nothing you enter is sent anywhere.
Who runs Exchange Calculators?
Sports Trading OS, a UK educational publisher that teaches betting-exchange trading as probability management, not prediction. This site is the free tools shelf; the teaching lives at sportstradingos.com.
Do these calculators help me win?
No, and anyone who says their calculator does is selling something dishonest. These tools do the arithmetic of exchange betting — stakes, liabilities, hedges, costs — correctly and instantly. Whether a price is worth taking remains entirely your judgement and your risk.