Very Good Dice Roller

Use Very Good Dice Roller for your dice rolling needs, or do not. I am not a beggar.

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Randomness Test Configuration

Test Cycles: (20-100 available)

Algorithm:

This tool tests the randomness of the random number generator used throughout this site. The results are indicative of the randomness quality you can expect from your game rolls.

To test the randomness of the generator, we select 6 dice types and roll each one 10,000 times. The observed results are then compared to the expected results. If the observed results are statistically within a 95% confidence interval of the expected results, then the roll has passed the test. However, about 5% of observed rolls will result in a failed test, even with a perfectly random generator. With 6 dice being rolled, this means that you can expect about 1 in 4 cycles to include at least one dice failing due to normal statistical variation.

To account for this, we run multiple cycles to see if failures happen at the right rate. If your dice are truly random, failures should occur at approximately 25% across all cycles. When running the test, if your failure rate falls within a 95% confidence interval of that 25% figure, then you can be confident that the randomness generator is truly random.

You can choose to use two algorithms and different numbers of cycles for the test. We recommend using the Mersenne Twister for the test and for your dice rolls, as it is the more reliable of the two algorithms. We also recommend using 100 cycles for your randomness testing as this will provide the most robust outcomes. However, this will take longer to complete, so you can reduce the number of cycles if needed.

Status: Preparing test...

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