Betting Odds Converter

How to use

1. 1Pick the input format (American, Decimal, Fractional, or Implied %) and type the price you want to convert. The other three formats update instantly.
2. 2Use the quick preset chips (+100, -110, +200, +500, -200) to load the most common prices without typing.
3. 3Enter a stake amount and pick a currency to see your profit (winnings) and total return (stake plus winnings) for the converted price.
4. 4Optionally, type your own true win probability to see the edge over the implied price, the expected value per unit, the EV on your stake, and the fair odds that would match your probability.
5. 5Use the Parlay combiner to multiply two or more independent legs. Each leg can use a different input format, and the combined price is shown in all four formats with the parlay implied probability.

About this tool

Betting Odds Converter translates a single odds line into every common format used by sportsbooks worldwide, then layers a stake-to-payout breakdown, an edge / expected value helper, and a multi-leg parlay combiner on top. Type a price in any of the four formats (American moneyline like -110 or +200, Decimal like 1.91 or 3.00, Fractional like 11/10 or 5/2, or Implied probability like 52.38% or 0.40) and the other three update live. The internal canonical form is decimal odds, so every conversion routes through one well-tested formula and the round trip is loss-free for normal bookmaker prices. Fractional output is reduced to lowest terms with a search across denominators 1 through 200 so common UK prices like 5/2, 11/4, 13/8, and 100/30 render exactly the way a paper racing card prints them. Quick presets cover the five most-typed lines (+100 even, -110 standard juice, +200, +500, -200) so a visitor searching odds converter can see the math without entering a value. The Stake and payout section uses the formulas Profit = Stake x (Decimal - 1) and Total return = Stake x Decimal, with currency formatted via Intl in eight currencies (USD, EUR, GBP, CAD, AUD, JPY, INR, TRY). The Edge and expected value section accepts your own estimate of the true win probability and reports four numbers: Edge (your probability minus the implied probability), EV per unit (Decimal x TrueProb - 1, the standard +EV criterion), EV on the entered stake, and the fair odds the price should be at your probability. Edge and EV are color-coded so a positive number reads green and a negative number reads rose. The Parlay combiner multiplies up to twelve independent legs of decimal odds; each leg has its own input format dropdown so American, decimal, fractional, and implied prices can be mixed inside one slip. The combined price is shown in all four formats with the implied probability of the parlay hitting and a profit preview for the entered stake. Common pitfalls handled gracefully: a negative American line below 100 in magnitude is accepted and converted via the standard formula instead of being rejected, even-money inputs (EVEN, EVS, PK) shortcut directly to decimal 2.0, fractional input accepts both 5/2 and 5-2 separators, implied probability accepts decimals (0.40), percentages (40%), and bare numbers larger than 1 (treated as percentages so 40 becomes 0.40). All math runs locally in your browser. Useful for comparing prices between US and European sportsbooks, sanity-checking a parlay payout, sizing an EV bet, removing the vig from a two-way market by averaging implied probabilities, and any everyday conversion task that requires reading the same line in four different conventions.

Free to use. Works in your browser. No signup, no login.