Odds Converter

Enter a price in any format and this tool shows you the other three plus the implied probability — the chance the odds are assuming.

Reading the four formats

The same bet can be written four ways. None changes the actual price; they're just conventions used in different markets.

• Decimal (2.50): Your total return per unit staked, including the stake back. A 1-unit bet at 2.50 returns 2.50 (1.50 profit). This is the easiest format for comparing value, which is why most analysts use it.
• Fractional (3/2): Profit relative to stake. 3/2 means you win 3 for every 2 staked. Common in the UK and Ireland.
• American (+150): A positive number is how much profit you make on a 100 stake (+150 = 150 profit). A negative number (−200) is how much you must stake to win 100. Standard in the US.
• Implied probability (40%): The chance the price assumes. This is the number that matters most for betting decisions.

The formulas

• Decimal → implied probability: 1 ÷ decimal × 100
• Decimal → American: if decimal ≥ 2.00, (decimal − 1) × 100; otherwise −100 ÷ (decimal − 1)
• American → decimal: positive: (american ÷ 100) + 1; negative: (100 ÷ |american|) + 1
• Fractional → decimal: (numerator ÷ denominator) + 1

Why implied probability is the number that matters

Once you can read the implied probability behind a price, you can ask the only question that matters in betting: is the real chance higher than this? If your estimate of the true probability beats the implied probability, the bet has value. If it doesn't, the price is against you no matter how appealing the outcome looks.

That comparison is the core of value betting, and it's exactly what Tofiko's models do at scale — estimating true probabilities across hundreds of leagues and flagging where bookmaker prices are too generous.