Free Gambling Maths Tools
Seven calculators and verifiers that run entirely in your browser. Nothing is sent anywhere, nothing needs an account, and every one shows its working rather than returning an answer you have to trust.
The Tools
Wagering requirement calculator
Prices what clearing a bonus costs in house edge, and tells you when that exceeds the bonus itself.
Crash round verifier
Recomputes a crash round from its seeds and shows the HMAC digest, the integer and the multiplier.
Coin flip verifier
Recomputes a flip and shows the byte that decided it.
Dice odds calculator
Multiplier, expected value and win frequency for any target and house edge.
Mines odds calculator
Full payout table with survival odds for any mine count.
Plinko probability calculator
Exact bucket probabilities for any row count, and the RTP your own paytable produces.
Limbo target calculator
Win chance and expected value for any target multiplier.
Why These Work Differently
A casino’s own verifier could be built to return fair every time, so a tool that only gives a verdict proves nothing. Ours print the intermediate values, and those are identical at every casino regardless of how the final conversion differs.
The calculators follow the same principle. Each one states the formula it uses, so the output can be checked by hand rather than taken on faith. Where a figure varies by provider, the tool asks for your value instead of assuming one.
| Tool | What makes it different |
|---|---|
| Wagering requirement calculator | Handles four stacking multipliers. Most calculators handle the headline figure and the base. |
| Crash round verifier | Shows every intermediate value rather than returning a verdict, so you can compare against any casino's formula. |
| Coin flip verifier | The parity step is simple enough to repeat by hand, which makes it the clearest place to learn the scheme. |
| Dice odds calculator | Shows that expected loss per amount staked is identical at every win chance. |
| Mines odds calculator | Multipliers are derived from the odds rather than read off a casino's chart. |
| Plinko probability calculator | Takes your paytable rather than assuming one, since multipliers vary by provider. |
| Limbo target calculator | Makes the flat expected value across targets visible in one table. |
Nothing Leaves Your Browser
Every calculation runs client side. Seeds you paste into a verifier are never transmitted, logged or stored, which matters because a server-side verifier would be handling values tied to a real account.
You can confirm this by opening your browser’s network tab while using any of them. No request is made when you press the button.
Using These on Your Own Site
These are free to reference, quote and screenshot. If a tool is useful to your readers, link to it rather than copying the output, because the figures update as the underlying data does.
Our measured payout data is published under CC BY 4.0, so you can reuse the figures with credit and a link back. Full terms are on the payout benchmarks page.
Found an error in one of the formulas? That is worth telling us about, and we will correct it and date the correction. Our editorial standards cover how.
18+ only. Every game these tools cover carries a negative expected value by design, which several of them will show you directly. Free, confidential support is available at GambleAware.