- Maths reviewed by Josh Miller
- Tested by Diana Westfield
A middle betting calculator for two bets that can both win. Say you back Over 2.5 goals at 1.95 with one bookmaker and Under 3.5 goals at 1.40 with another. Exactly three goals and you’re paid twice. Anything else and one bet loses. With £50 and £70 the middle pays +£75.50, the other results cost about £22. Is that worth it? Only if three goals happens more than about 23% of the time. The free CasinoCalcs calculator does that sum for any two lines.
Middle betting, explained with numbers
There are three outcomes and the calculator prices each one. Only A wins (4+ goals): −£22.50. Only B wins (0 to 2 goals): −£22.00. Both win (exactly 3): +£75.50. Give each a chance and you have your expected profit.
In a match expecting 2.7 goals, a Poisson model puts three goals at 22%, four or more at 29%, and two or fewer at 49%. Plug those in and the expected profit comes to about −£0.70. Close to fair, and that’s not an accident. Bookmakers price goal lines off the same curve, so a middle on the main lines rarely gives you much.
Where the real middles come from
From lines that move. You took Over 2.5 on Tuesday, team news broke, and by Saturday the market is Over 3.0 or 3.5. Now the Under at the new line costs you little and the middle is wide. Same with handicaps: you backed a side at +1, the line moves to +2 against them, and backing the other side at −1.5 gives you a band where both bets win.
Basketball and other high-scoring totals middle more often, because each number lands less often but a move of three or four points is common.
Middle or arb?
If both “only A” and “only B” show a profit, it’s an arb, not a middle: you win something on every result and the middle is a bonus. That’s rare on goal lines. Most middles are a small, frequent loss against a big, rare win, which makes them closer to a value bet than free money. Check the “break-even” line and be honest about your middle chance.
For setting stakes so both sides return the same, use the hedge calculator. To estimate the chance of exact goal counts, the Poisson calculator gives you over/under probabilities from expected goals.
Two bets means twice the stake on the line. BeGambleAware.org can help if betting is getting on top of you.