# Free Betting Calculators & Casino Bonus Tools

URL: https://gambgenius.com/tools/
Updated: 2026-10-19
Source: GambGenius (https://gambgenius.com/). 18+ only. Cite figures with the page URL; RTP figures are provider-published and can vary by casino.

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Precise, private calculators that run entirely in your browser. No sign-up, no tracking — just the numbers you need before you bet.

## [Odds converter](https://gambgenius.com/tools/odds-converter/)

Convert between decimal, fractional and American odds, see implied probability and calculate returns for any stake.

Sample: 2.50 decimal is 3/2 fractional, +150 American and a 40.0% implied chance.

Try decimal odds 

Fractional · American **3/2 · +150**
Implied probability 40.0%

[Open converter ](https://gambgenius.com/tools/odds-converter/?odds=2.50)

## [Wagering requirement calculator](https://gambgenius.com/tools/wagering-calculator/)

Work out total wagering, expected loss and the true expected value of any casino bonus before you claim it.

Sample: a $100 bonus at 30x needs $3,000 of bets; on average that costs $120 at 96% RTP.

Bonus $100 

Wagering 30x 

Required wagering $3,000
Average cost at 96% RTP $120

[Open calculator ](https://gambgenius.com/tools/wagering-calculator/?dep=100&match=100&max=100&x=30&applies=bonus&rtp=96&contrib=100)

## [Free spins calculator](https://gambgenius.com/tools/free-spins-calculator/)

Work out the expected value of free spins from the number of spins, spin value, RTP and wagering on the winnings.

[Open free spins calculator ](https://gambgenius.com/tools/free-spins-calculator/)

## [Slot cost calculator](https://gambgenius.com/tools/slot-cost-calculator/)

Work out the average hourly cost of playing a slot, for budgeting.

[Open slot cost calculator ](https://gambgenius.com/tools/slot-cost-calculator/)

## [Free bet calculator](https://gambgenius.com/tools/free-bet-calculator/)

Work out the returns and value of a stake-not-returned or stake-returned free bet.

[Open free bet calculator ](https://gambgenius.com/tools/free-bet-calculator/)

## [Bet calculator](https://gambgenius.com/tools/bet-calculator/)

Work out the returns for singles, doubles, trebles and accumulators, with each-way and the combined bookmaker margin.

[Open bet calculator ](https://gambgenius.com/tools/bet-calculator/)

## [Bonus terms checker](https://gambgenius.com/tools/bonus-checker/)

Work out the terms of any casino bonus, read from the text you paste into match, wagering, max bet, expiry and caps, then valued.

[Open bonus terms checker ](https://gambgenius.com/tools/bonus-checker/)

## [Video poker pay tables](https://gambgenius.com/tools/video-poker-pay-tables/)

Look up the published return and house edge of a video poker pay table from its full house and flush payouts.

[Open video poker pay tables ](https://gambgenius.com/tools/video-poker-pay-tables/)

## Gambling should stay fun

Set deposit limits before you play, never chase losses and take regular breaks. If gambling stops being enjoyable, free and confidential help is available 24/7.

[Responsible gambling tools ](https://gambgenius.com/responsible-gambling/)