Betting calculator

Free Bet Calculator

Use this free bet calculator to work out the lay stake, lay liability and expected profit from a free bet, including stake-not-returned free bets.

Quick explanation: Many bookmaker free bets are stake not returned, meaning only the profit part is paid if the bet wins. This calculator helps show the difference.

Enter your free bet details

Choose whether the free bet stake is returned, then enter the back odds, lay odds and exchange commission.

Lay stake £45.62
Lay liability £205.29
If free bet wins £44.71
If free bet loses £44.71
Conversion rate 89.41%

This stake-not-returned free bet converts to about £44.71 profit, or 89.41% of the free bet value.

What is a free bet calculator?

A free bet calculator helps work out how much to lay on a betting exchange when using a bookmaker free bet. It shows the lay stake, lay liability, and the expected profit if the free bet wins or loses.

This is useful because many free bets do not return the stake. A £50 stake-not-returned free bet at odds of 6.00 does not pay a £300 return. It usually pays £250 profit if it wins.

Stake not returned formula

Lay stake = free bet stake × (back odds − 1) ÷ (lay odds − commission)

Lay liability = lay stake × (lay odds − 1)

If free bet wins = free bet profit − lay liability

If free bet loses = lay stake after commission

Stake not returned vs stake returned

Free bet type What happens if it wins? Common use
Stake not returned Only the profit part is paid. Common bookmaker free bet offers.
Stake returned / cash bet The stake is included in the return. Normal cash bets or some bonus types.
Important: Free bet terms vary. Always check minimum odds, expiry dates, eligible markets, settlement rules and whether the stake is returned.

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