Tools
Betting calculators, free to use and free to embed
A suite of fast, accurate betting calculators — matched betting, arbitrage, expected value, Kelly and an odds converter — plus a live demo of the oddsmatcher. Every calculator runs entirely in your browser; each drops in with a single snippet, themed to your brand.
01 — Calculators
Matched betting & offers
Turn sign-up offers and free bets into locked profit — lay at the exchange, or scan the oddsmatcher.
Matched betting calculator
FreeWork out your lay stake, liability and locked profit in one place.
Open the matched betting calculatorEach-way calculator
FreeSee your return if a selection wins, places, or doesn't.
Open the each-way calculatorOddsmatcher (demo)
DemoSee the shape of the matched feed, with sample data.
Open the oddsmatcher (demo)02 — Calculators
Arbitrage, dutching & value
Find and size guaranteed, dutched or value bets across bookmakers.
Arbitrage calculator
FreeSplit your stake across outcomes to lock a guaranteed return.
Open the arbitrage calculatorDutching calculator
FreeBack several selections for the same return whichever wins.
Open the dutching calculatorExpected value calculator
FreeTurn your probability estimate into expected profit and an edge.
Open the expected value calculatorKelly stake calculator
FreeSize your stake to your edge — full, half or quarter Kelly.
Open the kelly stake calculator03 — Calculators
Odds & analysis
Convert prices, combine selections, and read the margin baked into a market.
Odds converter
FreeDecimal, fractional, American and implied probability — instantly.
Open the odds converterAccumulator calculator
FreeCombine your selections to see the combined odds and return.
Open the accumulator calculatorMargin & fair-odds calculator
FreeSee the margin baked into a market and the true, no-vig prices.
Open the margin & fair-odds calculatorFor platforms & tipsters
Embed any tool, brand it as yours.
The calculators are framework-free and style-isolated — one <script> tag and a host element drops a fully-themed widget into any page. Five presets plus your own accent, surface, text and radius. The live oddsmatcher embeds under your own feed key, filtered in the browser.
Explore the widget product & playground
18+ · Data product for licensed operators. Please gamble responsibly.
Want the live feed behind the oddsmatcher
The calculators are free forever. When you need real, pre-matched opportunities across deep UK coverage with bet365 included, start a free trial or tell us what you're building.