Decimal to American Odds Converter

The formula

There are two formulas, depending on whether the decimal value is at or above 2.0 (the underdog/longshot side, where American odds are positive) or below 2.0 (the favorite side, where American odds are negative):

Decimal ≥ 2.00 (underdog / longshot). American = (Decimal − 1) × 100
Example: 2.50 → (2.50 − 1) × 100 = +150
Decimal < 2.00 (favorite). American = −100 / (Decimal − 1)
Example: 1.50 → −100 / 0.50 = −200

Conversion table

Common odds across all three formats. Use this as a quick reference; the calculator above handles any value to four decimal places of precision.

Decimal	American	Fractional
1.10	-1000	1/10
1.25	-400	1/4
1.40	-250	2/5
1.50	-200	1/2
1.67	-150	4/6
1.75	-133	3/4
1.83	-120	5/6
1.91	-110	10/11
2.00	+100	1/1 (Evens)
2.10	+110	11/10
2.25	+125	5/4
2.50	+150	6/4
3.00	+200	2/1
3.50	+250	5/2
4.00	+300	3/1
5.00	+400	4/1
6.00	+500	5/1
11.00	+1000	10/1
21.00	+2000	20/1
51.00	+5000	50/1
101.00	+10000	100/1

When to use decimal odds

Decimal odds are the standard format on most European, Asian, Australian and Canadian sportsbooks. They are the easiest to do mental math with — multiply your stake by the decimal value to get total payout.

When to use American odds

American odds are the universal format at U.S. sportsbooks and across U.S. media. Sharp bettors and oddsmakers in the U.S. think in moneyline (American) terms.

Frequently asked questions

Why does decimal 2.00 equal American +100?

Both represent a 50% implied probability. A $100 bet at decimal 2.00 returns $200 total ($100 profit). A $100 bet at +100 returns $200 total ($100 profit). Same payout, different notation.

What does decimal 1.91 mean in American?

1.91 ≈ −110 in American — the standard "juice" or "vig" line at U.S. sportsbooks for evenly priced markets.

Are decimal 1.00 odds possible?

No — decimal 1.00 implies 100% probability and zero payout. The lowest realistic decimal is around 1.01 (≈ −10000 American, near-certain favorite).

How do I convert in my head?

For decimal ≥ 2.0: subtract 1, multiply by 100. For decimal < 2.0: divide 100 by (decimal − 1) and put a minus sign. So 1.40 → 100 / 0.40 = 250 → −250.