Decimal Odds Converter & Calculator
Convert freely between decimal (European), fractional (UK), American moneyline and implied probability odds — type any one format and get the other three instantly. Plus payout, parlay, no-vig fair odds and each-way calculators below.
Odds converter — type any format
Payout for these odds
Profit = stake × (decimal − 1). Total return = stake × decimal.
Common odds — quick reference
| Decimal | Fractional | American | Implied probability |
|---|---|---|---|
| 1.5 | 1/2 | -200 | 66.6667% |
| 2 | 1/1 | +100 | 50% |
| 2.5 | 3/2 | +150 | 40% |
| 3 | 2/1 | +200 | 33.3333% |
| 5 | 4/1 | +400 | 20% |
| 11 | 10/1 | +1000 | 9.0909% |
Generated from the same verified formulas as the converter above.
Parlay calculator (2–8 legs)
Enter each leg as decimal odds. Combined odds = product of all legs.
No-vig (fair odds) calculator
Enter the decimal odds of every outcome of one event (2–8). We remove the bookmaker margin and show the true fair probabilities and fair odds.
| Outcome | Implied | Fair prob. | Fair decimal |
|---|
Each-way calculator (simple)
Stake is split in half: one win bet at full odds, one place bet at reduced odds. Standard place terms: 1/4 or 1/5 of the win odds.
Vig / juice / overround — explained with numbers
A bookmaker prices every outcome a little shorter than fair, so the implied probabilities add up to more than 100%. The excess is the overround — the bookmaker's margin (also called vig or juice).
Fair probability = implied ÷ total implied. Fair decimal = 1 ÷ fair probability. In the example, the true 50/50 event is priced at 1.9091 instead of the fair 2 — that gap is the bookmaker's edge.
Formulas used
- Decimal = 1 + fractional (e.g. 3/2 → 1 + 3/2 = 2.50)
- Fractional from decimal: decimal − 1, simplified (2.50 → 3/2)
- American +X → 1 + X/100 (e.g. +150 → 2.50); American −X → 1 + 100/|X| (e.g. −200 → 1.50)
- Decimal → American: d ≥ 2.00 → +(d−1)×100; d < 2.00 → −100/(d−1)
- Implied probability = 1 ÷ decimal (2.50 → 40%)
- Profit = stake × (decimal − 1); total return = stake × decimal
- Parlay combined = product of leg decimals
- No-vig: fair_p = implied ÷ Σimplied; fair decimal = 1 ÷ fair_p
- Each-way: half stake @ full decimal + half stake @ (1 + (decimal−1) × place fraction)
Frequently asked questions
What are decimal odds?
Decimal odds, also called European odds, show your total return for every 1 unit staked, with the stake included. Decimal odds of 2.50 mean a winning 1 stake returns 2.50 in total: 1.50 profit plus your 1 stake back.
How do I convert decimal odds to fractional odds?
Subtract 1 from the decimal odds, then simplify the result as a fraction. Decimal 2.50 becomes 1.50, which simplifies to 3/2. Decimal 3.50 becomes 2.50, which is 5/2.
How do I convert decimal odds to American (moneyline) odds?
If the decimal odds are 2.00 or higher, the American odds are +(decimal - 1) x 100, so 2.50 becomes +150. If the decimal odds are below 2.00, the American odds are -100 / (decimal - 1), so 1.50 becomes -200.
What does -110 mean in decimal odds?
American odds of -110 convert to decimal 1 + 100/110 = 21/11 = 1.9091, which bookmakers usually display rounded as 1.91. It is the classic even-money price with the bookmaker margin built in.
How do I convert American odds to decimal odds?
For positive moneyline odds +X, decimal = 1 + X/100, so +150 becomes 2.50. For negative moneyline odds -X, decimal = 1 + 100/X where X is the number without the sign, so -200 becomes 1 + 100/200 = 1.50.
What is implied probability?
Implied probability is the chance the odds suggest, calculated as 1 divided by the decimal odds. Decimal 2.50 implies 1/2.50 = 40%. Decimal 1.50 implies 66.6667%. It is not a prediction, just the price translated into a percentage.
What is the vig, juice, or overround?
The vig (also called juice) is the bookmaker margin. Every outcome is priced a little shorter than fair, so the implied probabilities add to more than 100%. The excess is the overround. Example: when both sides of an event are priced at 1.91, each side implies 52.356%, the total is 104.712%, and the overround is 4.712%.
What are fair (no-vig) odds?
Fair odds remove the margin. Divide each implied probability by the total: fair probability = implied / total implied, then fair decimal = 1 / fair probability. In the 1.91 vs 1.91 example, each side's fair probability is 50% and the fair decimal odds are 2.
How are parlay odds calculated?
Multiply the decimal odds of every leg. A 3-leg parlay at 1.50 x 2.00 x 2.50 gives combined decimal odds of 7.5, with an implied probability of 13.3333%. A 20 stake on it returns 150.00 total (130.00 profit).
How does the each-way calculator work?
Your stake is split in two: half goes on the win at full decimal odds, half on the place at reduced odds, usually 1/4 or 1/5 of the win odds. Example: a 100 stake at 11.00 with 1/4 place terms gives place odds of 3.5. If it wins you get 725.00 back; if it only places you get 175.00 back.
How is the payout calculated from decimal odds?
Profit = stake x (decimal - 1). Total return = stake x decimal, which includes your stake. A 100 stake at 2.50 returns 250.00 total: 150.00 profit plus the 100 stake.
Is this tool betting advice?
No. This is an educational odds converter and calculator. It does not recommend bets, and converted odds say nothing about who will win. Never bet money you cannot afford to lose, and seek help from a local problem-gambling support organisation if gambling stops being fun.
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