Planning estimate only, not financial, tax, or legal advice. Verify assumptions and current rules before making decisions.
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How this calculator works
Formula
Each flip reads a 32-bit unsigned integer from the browser Web Crypto random-value source. Values below half the unsigned range map to Heads; values at or above half map to Tails, giving equal-size outcome ranges.
Worked example
For deterministic test values [0, 4294967295, 1, 3000000000], the mapped sequence is Heads, Tails, Heads, Tails: two of each and a longest streak of one.
Sources
Assumptions to verify
- Each browser-generated 32-bit value is mapped independently to one of two equal-size ranges.
- Short samples can be uneven and can contain streaks even when the process is fair.
- The tool is for casual decisions and simulations, not regulated gaming, auditing, or key generation.
Frequently asked questions
Why was my batch not exactly 50/50?
Randomness describes long-run probabilities, not a promise that every short batch contains equal counts.
Are flips sent to a server?
No. Random values and results are generated and processed locally in the browser.
Can I use this for gambling or security keys?
No. It is designed for casual choices and simulations, not regulated outcomes, audits, lotteries, or cryptographic key management.
Privacy: Inputs and results stay in this browser. Any future sponsored recommendation or advertisement will be clearly labeled and kept separate from the calculation.