# Fractional and decimal odds: what 5/1, 6.00 and evens mean

> Fractional odds such as 5/1 equal decimal odds of 6.00. Conversion formulas, evens, implied probability and a table of invented examples, rounded half up.

Source: https://bookieledger.com/terms/odds-formats/
Updated: 2026-11-07

Fractional odds show profit against stake: 5/1 pays €5 profit on a €1 stake. Decimal odds show the total return per €1 staked, so 5/1 is 6.00. Evens is 1/1, or 2.00. To convert, add 1 to the fraction. One divided by the decimal price gives the implied probability, 16.67% for 6.00.

## What are the two formats?

In fractional odds a/b, you win a for every b staked, and you also get your stake back. In 5/1, a stake of €1.00 wins €5.00 profit.

In decimal odds, the number is the total return for a stake of 1, stake included. At 6.00, a stake of €1.00 returns €6.00.

Evens means 1/1: the profit equals the stake. In decimal it is 2.00. Write it as "evens (2.00)".

**Bottom line:** Fractional shows profit per stake; decimal shows total return per stake, stake included.

## How do you convert between them?

- Fractional a/b to decimal: 1 + a/b.
- Decimal to fractional: subtract 1, then write the result as a fraction.
- Implied probability: 1 divided by the decimal odds. For a fraction, b divided by (a + b).

Results are rounded to two places, half up.

**Bottom line:** Decimal equals 1 plus the fraction; implied probability equals 1 divided by decimal.

## What do the conversions look like?

The prices are invented examples, not offers.

**Conversion examples. Source: derived by Bookie Ledger from the formulas above, invented prices · Checked 7 November 2026**

| Fractional | Decimal | Implied probability |
|---|---|---|
| 5/1 | 6.00 | 16.67% |
| 11/4 | 3.75 | 26.67% |
| 9/4 | 3.25 | 30.77% |
| Evens (1/1) | 2.00 | 50.00% |
| 10/11 | 1.91 | 52.38% |
| 1/2 | 1.50 | 66.67% |

Going the other way, a decimal price of 3.50 minus 1 is 2.50, which is 5/2.

On a €10.00 stake at 11/4 (3.75), a win returns €37.50 in total: €27.50 profit plus the stake.

**Bottom line:** 5/1 is 6.00, 11/4 is 3.75 and evens is 2.00, all by the same formula.

## Which format does a site show?

An operator chooses how to display odds and may let you switch. We have not yet recorded the display format used by three operators for customers in Ireland: could not be verified on 7 November 2026.

Convert to one format before you compare prices (see [comparing odds fairly](https://bookieledger.com/terms/how-to-compare-odds-fairly/)). Our bet slip simulator and expected value calculator accept both formats.

**Bottom line:** Convert first, then compare; operator display formats are not yet recorded.

## Where to go next

- [Comparing odds fairly](https://bookieledger.com/terms/how-to-compare-odds-fairly/)
- [Bonus cash and credited stakes: how the terms treat them](https://bookieledger.com/terms/free-bet-vs-bonus-cash/)
- [Qualifying bet, minimum odds and expiry: the conditions](https://bookieledger.com/terms/are-free-bets-really-free/)

## Sources

- Formulas and examples: derived on this page from the stated definitions.
- Operator display formats: not yet recorded.

## What changed

7 November 2026: first version. No later changes recorded.