PHTAYA Sports Odds: How to Read Betting Odds in Three Formats

A betting slip only tells you what you might win once you can read the number sitting next to the team name. How to read betting odds comes down to three formats — decimal, fractional and American — and one formula that turns any of them into a probability. This page walks through all three, converts between them, and works a peso example so the maths is never abstract.

None of the figures below come from a live market. They are worked examples built to show the conversion, and every one is labelled as such.

How to Read Betting Odds: Decimal, Fractional and American Formats

Every odds format answers the same question — what does this price imply about the chance of the outcome, and what does it pay? They just phrase the answer differently.

Format	What the number shows	Example	Decimal equivalent
Decimal	Total payout per 1 unit staked	2.50	2.50
Fractional	Profit as a ratio to the stake	3/2	2.50
American	Profit per 100 (plus) or stake needed for 100 profit (minus)	+150	2.50

All three rows describe the exact same price. Once you can convert between them, the format on screen stops mattering. Decimal odds are the default across most of Asia and Europe, fractional odds are the traditional UK format, and American odds are the standard on US sportsbooks — a market can show any one of the three depending on where the book is based.

Decimal Odds: The Format Most Markets Show First

Decimal odds are the simplest to read because the number already includes your stake. Multiply the stake by the decimal price and the result is the full return, not just the profit.

1. Take the decimal price, for example 1.91.
2. Multiply it by the stake: a hypothetical ₱500 stake at 1.91 returns ₱955.
3. Subtract the stake to find profit: ₱955 − ₱500 = ₱455.

A decimal price below 2.00 always means the profit is smaller than the stake — that side is priced as the favourite.

Fractional Odds and Converting Them to Decimal

Fractional odds (5/2, 1/4, 3/1) show profit relative to stake rather than total return, which is why they need one extra step before you can compare them to a decimal price.

The conversion is (numerator ÷ denominator) + 1:

• 5/2 → (5 ÷ 2) + 1 = 3.50 decimal, which implies a 28.57% chance.
• 1/4 → (1 ÷ 4) + 1 = 1.25 decimal, which implies an 80.00% chance.

A fraction with a bigger top number than bottom number (5/2) is an underdog price; a fraction with a smaller top number (1/4) is a heavy favourite.

American Odds: Reading the Plus and Minus Signs

American (moneyline) odds use a plus or minus sign in front of a three-digit number, and the sign changes which formula applies.

Sign	Formula to decimal	Worked example
Plus (+130)	(number ÷ 100) + 1	(130 ÷ 100) + 1 = 2.30
Minus (−150)	(100 ÷ number) + 1	(100 ÷ 150) + 1 = 1.67

A minus number is always the favourite and shows how much you’d need to stake to profit 100; a plus number is always the underdog and shows how much profit a 100 stake returns. The full moneyline mechanic, including favourite and underdog pricing on a hypothetical basketball matchup, sits on the moneyline betting page linked below.

Implied Probability: Betting Odds Explained as a Percentage

Betting odds explained in plain terms means turning any price into a percentage chance, and the formula is the same regardless of format: implied probability = 1 ÷ decimal odds.

Decimal price	Implied probability
1.20	83.33%
1.50	66.67%
1.91	52.36%
2.50	40.00%
3.00	33.33%

Add up the implied probabilities on both sides of a two-outcome market and the total sits above 100% — that gap is the sportsbook’s built-in margin, worked through with a two-way and a three-way example on the betting margin page.

A Peso Example Across All Three Formats

Suppose the same team is priced at 1.91 decimal, 10/11 fractional and −110 American — three formats, one price.

1. Decimal 1.91 on a ₱1,000 stake returns ₱1,910 total, a ₱910 profit.
2. Fractional 10/11 converts to (10 ÷ 11) + 1 = 1.909, which rounds to the same 1.91 decimal price.
3. American −110 converts to (100 ÷ 110) + 1 = 1.909, again the same price.

Whichever format a market displays, the conversion formulas above land on the same number. Rounding is the only reason the three don’t match to the decimal place every time: fractional and American prices sometimes round to a decimal figure that carries one extra digit, which is why 10/11 and −110 both settle at 1.909 rather than a clean 1.91.

Where This Sits on PHTAYA’s Lobby

PHTAYA’s desktop menu lists a Sports tab alongside Slots, Fishing and Live Casino, and the mobile category tabs carry the same Sports entry. This page teaches the maths behind any odds format, not the specific markets or odds format that tab displays — for that, open the tab itself. Two things worth checking before you rely on any price it shows:

1. Whether the tab offers a format switch (decimal, fractional or American) before you assume one.
2. Whether the market lists a draw as a third outcome, which changes the implied-probability maths from two-way to three-way.

Odds only matter once a balance is funded and a bet is placed with a clear head. If chasing a loss after a bad read of the odds sounds familiar, the loss chasing pattern page covers how that spiral starts and how to stop it, and PHTAYA’s own responsible gaming page lists the PAGCOR self-exclusion options available to any player who wants a break.

Read the Rest of This Cluster

Each spoke below takes one odds format further into a worked example:

1. How moneyline betting prices a favourite against an underdog, on a hypothetical NBA matchup.
2. How spread betting settles a half-point line against a whole-point one, on a hypothetical PBA scoreline.
3. How a sportsbook’s betting margin gets baked into every price, with a two-way and a three-way market.

For the fine print that decides whether a settled bet even counts toward a deposit turnover rule, PHTAYA’s casino fine print pillar covers valid bets, game weighting and more, starting with what counts as a valid bet. To see what’s actually on the lobby beyond the Sports tab, browse PHTAYA’s own games list.