How Betting Odds Work

Decimal odds: what the number actually means

Every price you see on an AFL, NRL, cricket or Premier League market is a decimal multiplier. Multiply your stake by the odds to get your total return.

• $1.50 × $20 stake = $30 return ($10 profit)
• $2.00 × $20 stake = $40 return ($20 profit) — this is an even-money bet
• $4.50 × $20 stake = $90 return ($70 profit)

Anything under $2.00 means the outcome is favoured (you risk more than you win). Anything over $2.00 means it's the underdog side of the market. A price of exactly $2.00 is a coin-flip in the bookmaker's eyes, before margin.

Decimal always includes your stake in the return figure, which is why it's the standard across Australian wagering — no separate 'plus your stake back' mental maths like fractional or American formats.

Turning odds into implied probability

The real value of understanding odds is converting them into a percentage chance. The formula is simple:

Implied probability = 1 ÷ decimal odds

• $1.50 → 1 ÷ 1.50 = 0.667 = 66.7%
• $2.00 → 1 ÷ 2.00 = 0.50 = 50%
• $4.50 → 1 ÷ 4.50 = 0.222 = 22.2%

That percentage is the break-even line. If you think a Big Bash side priced at $2.00 (50%) actually wins 58% of the time, the price is in your favour. If you think it wins only 45% of the time, you're taking the worse side of the bet. This is the whole game: comparing your own read of a fixture against the number the bookmaker is offering. Our predictions and market movers pages exist to help you judge whether a price is drifting for a reason.

The bookmaker margin (and why the percentages add up to more than 100%)

Add up the implied probabilities of every outcome in a market and you'll get a figure above 100%. The extra is the bookmaker's margin — the built-in edge that funds the business.

Take a two-way market like a tennis match with no draw:

• Player A: $1.80 → 55.6%
• Player B: $2.10 → 47.6%
• Total: 103.2%

That 3.2% over 100 is the margin (also called the overround or vig). On a three-way football market — home, draw, away — the margins are usually larger because there are three prices each carrying a slice.

The lower the margin, the closer the odds sit to true probability, and the more of your stake works for you over time. This matters far more than a one-off big price, because you pay it on every single bet.

Margins across Australian bookmakers: the numbers

We track the average margin and how often each bookmaker posts the top price across a sample of markets. Lower average margin is better for the punter; higher best-price share means that book is more often the sharpest number on the board.

• Sportsbet — 4.91% average margin (44 markets sampled)
• PointsBet — 5.64% (51 markets)
• Neds — 5.89% (59 markets)
• Ladbrokes — 5.82% (258 markets)
• Unibet — 5.84% (243 markets)
• PlayUp — 5.93% (44 markets)
• TAB — 6.05% (59 markets)
• betr — 6.19% (56 markets)
• bet365 — 7.44% (30 markets)

Best-price share tells a different story. Across a large sample, Unibet topped the board 56.0% of the time and Ladbrokes 54.7% — meaning on any given market these two frequently hold the leading price. Neds led 35.6% of the time, TAB 27.1%, and bet365 23.3%.

The takeaway: the book with the lowest headline margin isn't automatically the one showing the best price on your specific game. That's why comparing prices per fixture beats loyalty to one account.

A worked example: comparing the same game

Say an A-League home side is priced across three books:

• Ladbrokes: $2.30 → 43.5% implied
• Unibet: $2.25 → 44.4% implied
• bet365: $2.20 → 45.5% implied

On a $50 stake:

• $2.30 returns $115 ($65 profit)
• $2.25 returns $112.50 ($62.50 profit)
• $2.20 returns $110 ($60 profit)

Same bet, same outcome — $5 difference in profit just from where you placed it. Over a season of hundreds of bets, taking the best available price on each one is the single biggest controllable edge a punter has. That's the argument for line-shopping across bookmakers rather than sticking with whichever app opened first.

Note: bookmaker margins and prices move constantly with money and team news. Always check the live price before placing a bet — our betting odds pages pull current numbers for today's fixtures.

Odds move — and the movement tells you something

Prices aren't fixed. When a favourite firms (shortens, e.g. $2.10 into $1.85), money and confidence are flowing that way. When a price drifts (lengthens, e.g. $2.10 out to $2.40), the market is cooling on that outcome — sometimes on a late team change, a scratching in racing, or weather affecting a cricket surface.

Watching market movers helps you spot where informed money is landing before kick-off. It doesn't guarantee a result, but a sharp move against public sentiment is worth understanding before you back the other side.

Live odds and how they recalculate

During a match, odds update continuously as the situation changes. A footy side that scores early sees its price shorten instantly because its implied probability of winning has jumped. Live betting markets carry slightly higher margins than pre-match, because the bookmaker is pricing a moving target and needs a buffer against sudden swings.

Most Australian books — including bet365, Sportsbet, Ladbrokes, Unibet, TAB and Neds — run live betting, and several offer Cash Out, which lets you settle a bet early at the current live value rather than waiting for full time. Cash Out prices bake in the same margin logic, so the offer to close is always a little below the mathematically 'fair' live value.

Odds, bet builders and multis

When you combine selections, the odds multiply. A three-leg multi at $1.50, $1.80 and $2.00 gives combined odds of 1.50 × 1.80 × 2.00 = $5.40. The catch is the margin compounds too — you're paying the bookmaker's edge on every leg, so multis are higher-variance and lower-value over time than singles.

Bet Builder markets (offered by bet365, Sportsbet, Ladbrokes and Unibet) work the same way, pricing correlated outcomes within a single game. The final price reflects the combined probability of all your legs landing, adjusted for how the legs relate to each other.