Recalculate a completed round: choose Stake Crash or a supported Bustabit scheme, paste the round's game hash, and compare the calculated multiplier with the recorded result. You can also check a SHA-256 commitment. Calculations run locally in your browser; the tool does not upload or save the values you enter.
A matching multiplier confirms that the selected calculation reproduces the result from the supplied inputs. To check whether those inputs were changed, you also need a commitment recorded before the result was revealed. This tool supports the specific implementations listed below; it does not calculate Aviator or BC.Game crash points.
Choose a Verification Mode
Stake's published 2019 Crash scheme, with the Bitcoin block 584,500 salt and a fixed 1% house edge.
Calculation Result
Show calculation steps and hashes
How to Check a Round
- Identify the implementation. Open the game's fairness details and select the matching scheme. Stake Crash uses a different process from many single-player Stake Originals.
- Copy the disclosed game hash. Save the round number and displayed multiplier as well. If available, use the adjacent chain commitment that you recorded before the hash was revealed.
- Calculate and compare. A mismatch can come from the wrong scheme, a copied value, text-versus-byte encoding, or display precision. Recheck those details before drawing a conclusion.
A multiplier match and a chain-link match answer different questions. Neither establishes that a casino is solvent, that a withdrawal will be paid, or that an entire history was generated without bias. See what Provably Fair verification proves for the full process.
Supported Games and Limits
| Mode | Supported calculation | Scope |
|---|---|---|
| Stake Crash | 2019 salted-chain formula; Bitcoin block 584,500; 32-bit extraction; 1% edge. | Returns the published raw formula result in the steps and a two-decimal truncated display value. |
| Bustabit — 2025 salt | HMAC with the block 917,000 salt and raw game-hash bytes; 52-bit multiplier mapping. | Classic scheme after game 12,279,450; one-link checks hash raw bytes. |
| Bustabit — 2018 salt | HMAC with the block 505,750 salt and raw game-hash bytes; 52-bit mapping. | Previous chain; one-link checks hash the lowercase hexadecimal text. |
| SHA-256 Check | SHA-256 of UTF-8 text or decoded hexadecimal bytes, with an optional expected hash. | Digest or commitment comparison only; it does not produce a crash multiplier. |
Unsupported: Bustabit's Vx rounds require additional signature processing. Use Bustabit's official verifier for those rounds and for full chain audits. This tool also does not implement Aviator, BC.Game, Roobet or other providers' multiplier calculations. One coincidentally matching result does not establish compatibility.
Examples with Expected Results
Each button loads the complete input and expected result. Press Calculate and Compare to run it. Published chain anchors are used here as reproducible calculation inputs, not as claims about played rounds; the other game hashes are synthetic examples.
| Mode and input | Expected result | Action |
|---|---|---|
Stake published chain anchor78a9757d3be42b74a3f70239078ad9317125fe9ee630d5bdada46de963e56752 | 1.18×, truncated | |
Stake synthetic hash0576bbc6cdde4619a1e2533fd8a58f356094739b9794f6a06102b23e3d30c5e7 | 7.53×, truncated | |
Bustabit chain anchor, 2025 salt567a98370fb7545137ddb53687723cf0b8a1f5e93b1f76f4a1da29416930fa59 | 1.02× | |
Bustabit synthetic hash, 2025 salt274a58277eaf8bfdf9132f801027ac3e117d882ccd03829e7b81c58809612bbb | 2.25× | |
Bustabit previous-chain anchor, 2018 salt86728f5fc3bd99db94d3cdaf105d67788194e9701bf95d049ad0e1ee3d004277 | 8.35× | |
SHA-256 of the UTF-8 text test | 9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08 |
How the Calculations Work
Stake Crash
Stake's published seeding code uses the lowercase game-hash text as the HMAC key and the block-hash text as its message. Read the first eight hex digits of the digest as integer n, then calculate:
raw = max(1, (2^32 / (n + 1)) × 0.99)This tool also shows a value truncated to two decimals. Stake's short seeding-event code defines the raw formula without specifying every display detail, so retain the raw value when investigating a rounding mismatch. The Crash Game Algorithm Guide explains the mapping in more detail.
Bustabit
The supported classic schemes use the public salt as UTF-8 text for the HMAC key and the game hash as decoded bytes for its message. Read the first thirteen hex digits as integer r:
X = r / 2^52
multiplier = max(1, floor(99 / (1 − X)) / 100)The HMAC calculation and the chain-link check use different inputs: previous-chain links hash hexadecimal text, while the newer chain hashes bytes. Vx rounds additionally require a signature and are outside this tool's supported calculations.
SHA-256 Commitments
Text ab is two UTF-8 bytes; hexadecimal ab is one byte. Select the encoding specified by the platform. A digest match shows consistency with the expected value you supplied. Evidence that this value was published beforehand must come from your saved round record or the original commitment.
Frequently Asked Questions
Does a match prove the whole game was fair?
No. It confirms the selected calculation or hash comparison. Full verification also depends on the earlier commitment, the correct algorithm version, the source of the inputs and, where applicable, the rest of the chain. It does not guarantee withdrawals or eliminate the house edge.
Can I check Aviator or BC.Game here?
The multiplier modes do not support either game. Aviator's disclosed process includes SHA-512 and game-specific result mathematics; BC.Game publishes its own Crash mapping. A generic SHA-256 check may verify one disclosed commitment if its encoding matches, but it does not reproduce either game's complete result.
Why can the calculated result differ from the game?
Check the game hash, scheme, recorded multiplier and display precision. Bustabit's 2018, Vx and 2025 schemes are not interchangeable. If the exact documented process still disagrees with the round record, preserve the raw inputs and calculation steps for investigation.
Why do some results display 1.00×?
The formula and display precision can produce 1.00× without a separate divisibility rule. In the Stake model, about 1% of inputs are clamped to a raw value of 1. With the two-decimal truncation used here, values below 1.01 also display as 1.00×, bringing that displayed share to about 1.98%. Bustabit's supported mapping likewise displays 1.00× for about 1.98% of uniformly distributed extracted values. These are model probabilities, not measured frequencies or statements about bet settlement.
Does the tool predict future rounds?
No. It uses disclosed data from completed rounds. An earlier commitment does not reveal the hidden input needed to calculate the next result. Read why round history cannot provide that missing input.
Are my inputs sent anywhere?
The verifier code calculates with the browser's Web Crypto API and does not send, store or log your inputs. Other features on the website may make their own requests. You do not need an account, password, API key or unrevealed active seed to check a completed round.
Sources
- Stake Game Events and the 2019 Crash seeding event: formula, chain encoding and published salt.
- Bustabit multiplier code, salts and constants and chain and scheme handling.
- Bustabit's 2018 seeding event and September 2025 salt change.
For expected returns and the cost of the house edge, see the Crash Game RTP Guide.
This independent tool checks the documented calculations listed above. It is not a casino service or a guarantee of an operator's conduct. Gambling can cause financial harm; verification does not make a negative-expectation bet profitable. Responsible gambling information.