# Odds Converter: Decimal, Fractional & American

URL: https://gambgenius.com/tools/odds-converter/
Updated: 2026-10-19
Source: GambGenius (https://gambgenius.com/). 18+ only. Cite figures with the page URL; RTP figures are provider-published and can vary by casino.

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Enter odds in any format to instantly see decimal, fractional and American equivalents, the implied probability and your potential returns.

Odds format 

Odds e.g. 2.50

Stake ($)$ 

Implied probability
40.0%

Decimal
2.50
Fractional
3/2

American
+150
Total return
$25.00

A $10 bet returns $25.00, including $15.00 profit.

Tracking your bets? Members can log odds and closing prices in the [bet journal](https://gambgenius.com/account/journal/).

## Sign-up offers that accept odds of 2.50

Qualifying bets must be at or above each offer's minimum odds. 18+ · Ad.

Strikeline

Bet $10, Get $50 in Free Bets Min odds 1.50 (1/2)

18+. New customers. Min dep **$10**. Min odds **1.50 (1/2)**. Qualifying bet **$10**. Stake not returned. Free bets expire in **7 days**. Full T&Cs apply.

[Get offer ](https://gambgenius.com/go/strikeline/?p=odds-tool)
Apex Odds

Bet $20, Get $40 + Enhanced odds Min odds 2.00 (Evs)

18+. New customers. Min dep **$20**. Min odds **2.00 (Evs)**. Qualifying bet **$20**. Stake not returned. Free bets expire in **7 days**. Full T&Cs apply.

[Get offer ](https://gambgenius.com/go/apex-odds/?p=odds-tool)
Pitchside

Get $30 in Free Bets when you bet $10 Min odds 1.80 (4/5)

18+. New customers. Min dep **$10**. Min odds **1.80 (4/5)**. Qualifying bet **$10**. Stake not returned. Free bets expire in **7 days**. Full T&Cs apply.

[Get offer ](https://gambgenius.com/go/pitchside/?p=odds-tool)
Northstake

Up to $100 Money Back on your first bet Min odds 1.50 (1/2)

18+. New customers. Min dep **$10**. Min odds **1.50 (1/2)**. Refund as cash up to **$100**. Full T&Cs apply.

[Get offer ](https://gambgenius.com/go/northstake/?p=odds-tool)

## How to convert betting odds

Formulas

Fractional → decimal: (numerator ÷ denominator) + 1

American + → decimal: (odds ÷ 100) + 1

American − → decimal: (100 ÷ |odds|) + 1

Implied probability: 1 ÷ decimal × 100

## Odds conversion table

| Decimal | Fractional | American | Implied probability |
|---|---|---|---|
| 1.50 | 1/2 | −200 | 66.7% |
| 1.80 | 4/5 | −125 | 55.6% |
| 2.00 | 1/1 (Evs) | +100 | 50.0% |
| 2.50 | 6/4 | +150 | 40.0% |
| 3.00 | 2/1 | +200 | 33.3% |
| 4.00 | 3/1 | +300 | 25.0% |
| 6.00 | 5/1 | +500 | 16.7% |
| 11.00 | 10/1 | +1000 | 9.1% |

For a full walkthrough — including how to calculate the bookmaker margin on any market — read [betting odds explained](https://gambgenius.com/strategy/betting-odds-explained/), then learn to spot mispriced odds in our [value betting guide](https://gambgenius.com/strategy/value-betting/).

Questions

## Frequently asked questions

**How do I convert decimal odds to fractional?**

Subtract 1 from the decimal odds and express the result as a fraction. Decimal 2.50 minus 1 is 1.5, which is 3/2.

**How do I convert American odds to decimal?**

For positive American odds, divide by 100 and add 1 (+150 becomes 2.50). For negative odds, divide 100 by the odds without the minus sign and add 1 (−200 becomes 1.50).

**What is implied probability?**

Implied probability is the chance of an outcome suggested by the odds: 1 divided by the decimal odds. Odds of 4.00 imply a 25% chance.

**Why do implied probabilities add up to more than 100%?**

Because of the bookmaker's margin, or overround. The excess over 100% is the bookmaker's built-in edge on that market.

## Gambling should stay fun

Set deposit limits before you play, never chase losses and take regular breaks. If gambling stops being enjoyable, free and confidential help is available 24/7.

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