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Odds To Probability Converter

Translate odds and probability into the decimal price language used by binary outcome markets.

Last updated: 2026-05-04Last reviewed: 2026-05-04

Odds and probability converter

Odds implied probability
40.0%
Decimal outcome price
0.600

A binary outcome trading at 0.60 roughly maps to a 60% breakeven probability before fees, spreads, and settlement risk.

How this works

This converter translates American odds into implied probability and translates a probability estimate into the 0 to 1 decimal price format often used by binary outcome markets. Use it to normalize language before comparing markets, not to decide whether a price is attractive. The output is only a translation layer.

Positive American odds

100 divided by odds plus 100.

Negative American odds

Absolute odds divided by absolute odds plus 100.

Decimal outcome price

Probability percentage divided by 100.

Assumptions

  • American odds are entered without a plus sign.
  • Zero odds are treated as invalid and return zero probability.
  • The decimal price translation excludes fees, spreads, and settlement risk.

Do not ignore

  • Odds-implied probability includes bookmaker or market margin in many contexts.
  • Outcome markets can trade away from clean probability because liquidity, fees, and resolution risk matter.
  • Do not treat converted probability as a trade recommendation.

FAQ

Is a 0.60 price always a 60% chance?

It is a rough breakeven probability before frictions. Fees, spreads, liquidity, and settlement risk can all change the real threshold.

Why support American odds?

Many traders see event probabilities quoted as odds elsewhere and need a quick way to translate them into probability language.

Does this include edge or expected value?

No. Use the binary outcome EV calculator when you want to compare a market price with your own probability estimate.

What should I check after converting odds?

Check the live outcome market, settlement wording, spread, and calculator assumptions before treating a decimal price as usable.

Why can two markets show different probabilities?

Different fees, spreads, liquidity, participant mix, and settlement rules can make similar outcomes trade at different implied probabilities.

Next checks

Binary EV

Compare the converted probability with contract price and payout.

Prediction markets

Compare outcome-market mechanics with prediction-market venues.

Sources and corrections

See how outcome and probability claims are sourced and reviewed.

Risk notice
Outcome markets are high-risk event contracts. A market price is not a verified probability, the full cost can be lost, and resolution, settlement, liquidity, fees, and eligibility rules may alter the real risk.

Sources