Odds Converter: One Price, Three Formats and Its Real Chance
Tool · Odds
Type a price in decimal, fractional or American odds and the odds converter shows the other two formats, the implied probability and, when you enter every outcome of a market, the sportsbook's margin and the fair odds without it.
One pricethree formats
The same chance written three ways: 2.50 returns 150 profit per 100 staked.
Written by: Callum Reddaway·Checked by: Priya Lakshmanan·Updated
The odds converter below turns any price into the other two formats and into the probability it implies. Enter the prices of every outcome in a market and it also shows how much margin the sportsbook has built in, and what the fair odds would be without it. It runs in your browser; nothing you type leaves the page.
Odds converter
How the odds converter reads a price
Every format describes the same thing: how much a winning bet returns.
| Format | Example | What it says | Return on 10 USDT |
|---|---|---|---|
| Decimal | 2.50 | Total return per unit staked, stake included | 25 USDT |
| Fractional | 6/4 | Profit per unit staked, stake not included | 25 USDT |
| American | +150 | Profit on a 100 stake, or stake needed to win 100 | 25 USDT |
Decimal odds are the easiest to use with crypto because the arithmetic does not care what the unit is. A stake of 0.002 BTC at 2.50 returns 0.005 BTC; a stake of 40 USDT at 2.50 returns 100 USDT.
Working out the margin of a market
A fair market's implied probabilities add up to exactly 100 per cent. A sportsbook's add up to more, and the excess is its margin. Take a football match priced 2.30 for the home side, 3.40 for the draw and 3.20 for the away side:
- 1 / 2.30 = 43.5 per cent
- 1 / 3.40 = 29.4 per cent
- 1 / 3.20 = 31.3 per cent
Together they make 104.2 per cent, a margin of about 4.2 per cent. The odds converter does this for markets of up to six outcomes and shows the fair price of each outcome once the margin is spread in proportion to the prices. That spreading is an estimate; a sportsbook may load more margin onto one outcome than another.
Odds converter for accumulators
An accumulator's price is the product of its legs. Three legs at 1.85, 1.62 and 2.10 combine to 1.85 × 1.62 × 2.10 = 6.29, so a 20 USDT stake returns about 125.9 USDT if all three win. Convert each leg to decimal first, multiply, and then use the odds converter to turn the combined price back into fractional or American if that is the format you think in. Remember that the margin compounds too: three legs each carrying about 5 per cent leave the accumulator carrying roughly 15 per cent.
Why the margin matters more than the format
Two sportsbooks can show the same match in the same format at different prices. Over hundreds of bets, a difference of two or three per cent in margin outweighs almost any welcome offer. Comparing the margin on the markets you actually bet is the quickest way to see which sportsbook prices them more keenly.
Our guide to crypto betting odds explained works through more examples, including accumulators. The comparison of crypto betting sites on the home page covers the other things that decide where to bet, and the sports hub explains how settlement rules change from one sport to the next.
Converted prices are how you compare books. The best odds crypto betting sites board puts the converter's arithmetic to work, and live crypto betting sites explains why in-play prices carry more margin.
Once converted, a price can be turned into a return with the odds calculator or into a probability with the implied probability calculator.