HesapHanem

American to Decimal Odds Converter

Enter American odds like -150 or +200 to convert to decimal.

How it is calculated

For positive American odds the number is the profit on a 100 stake: decimal = 1 + odds ÷ 100. For negative odds it is the stake needed to win 100: decimal = 1 + 100 ÷ |odds|. Decimal odds include your stake, so they show the total return per 1 unit staked. The implied probability is 1 ÷ decimal × 100, shown as a percentage. The fractional odds come from the same numbers (odds : 100 for positive odds, 100 : |odds| for negative odds), reduced to lowest terms with the odds rounded to a whole number. Zero is not accepted. The implied probability includes the bookmaker's margin, so the probabilities of both sides of a market add to more than 100%. Decimal odds are rounded to two decimals for display only; the implied probability is worked from the unrounded value.

Worked example

American odds of −110 mean a stake of 110 wins 100. Decimal: 1 + 100 ÷ 110 = 1 + 0.9091 = 1.91 (1.9091 before rounding). So a 10 unit bet returns about 19.09 including the stake, a profit of 9.09. Implied probability: 1 ÷ 1.9091 = 52.38%, which equals 110 ÷ 210. The fractional form is 100/110, reduced to 10/11. Each side of a −110 / −110 market implies 52.38%, a total of 104.76%, and the extra 4.76% is the bookmaker's margin.

Try this example →

Common mistakes

  • Treating a negative number as a loss. The minus sign only says the price is a favourite, and the figure is the stake required to win 100, not an amount you lose.
  • Forgetting the sign. +150 and −150 are completely different prices (2.50 and 1.67 in decimal), so always include + or −.
  • Reading the implied probability as the true chance of winning. It contains the bookmaker's margin, so it is higher than the fair probability.
  • Entering odds between −100 and +100, such as +50 or −50. The tool converts them, but real American quotes are 100 or more in size, so such a value is probably a typo.
  • Confusing decimal odds with profit. 1.91 means a return of 1.91 per unit including the stake, so the profit per unit is only 0.91.

About this calculator

American (moneyline) odds and decimal odds are two of the main formats used to quote the same betting price, and converting between them just changes the arithmetic, not the underlying probability. For positive American odds (e.g. +200, the profit on a 100-unit stake), decimal odds = (American / 100) + 1; for negative American odds (e.g. −150, the stake needed to profit 100 units), decimal odds = (100 / |American|) + 1. Decimal odds directly represent the total payout per unit staked, including the original stake, which is why they’re favored on European and Asian betting exchanges.

From either format the implied win probability follows as 1 / decimal odds (expressed as a percentage), letting bettors judge whether a bookmaker’s price offers value against their own estimate of the true probability. Sportsbooks and bettors comparing lines across different platforms — US sportsbooks quoting moneylines, European ones quoting decimals, UK ones quoting fractions — rely on this conversion constantly; this calculator takes an American odds value and returns its decimal equivalent along with the implied probability and the equivalent fractional odds.

Was this helpful?

You can pick up to 3 reactions.

Comments (1)

  • Editorial team

    Implied probability includes the bookmaker's cut, which shows when you convert both sides of a market. Odds of +150 give 40.00% and -170 give 62.96%, which add to 102.96%, so the extra 2.96 points are margin. Convert each outcome before comparing prices between shops. A -150 line reads 1.67 decimal, 60.00% and 2/3. Would a reverse converter from decimal to American help?

Popular calculators

Loan Calculator

Monthly payment, total interest and full amortization schedule.

Percentage Calculator

Percent change, percent of, and ratio calculations.

Discount Calculator

Calculate final price, savings, and discount amount.

BMI Calculator

Body mass index from height and weight (metric or imperial).

Age Calculator

Compute your exact age in years, months and days from a birth date.

Compound Interest Calculator

Calculate the final amount and interest earned with compounding.

All Calculators