Calculate · Inspect · Experiment

Tools for thinking clearly about chance.

Change the inputs. See the result and its assumptions together. Download your calculation or simulation data.

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Count exact unordered combinations, with an optional separate number pool. Includes US and UK game presets.

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Convert a probability percentage into one-in-X chance and formal odds against, with clear denominators.

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Compare distinct complete lines in one draw with repeated independent draws, using stable probability arithmetic.

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Calculate the exact distribution of shared labels between two independent k-of-n draws.

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Calculate the chance of an adjacent pair or a run of at least three labels, with exact integer counting.

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Explore every odd/even category with exact combination counts and an accessible distribution table.

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Calculate absence probabilities and waiting-time expectations for one prespecified lottery label.

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Compare one specified label’s observed count with the mean and spread predicted by a binomial model.

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Generate a reproducible coin sequence or inspect your own, counting heads, runs and the longest repeated block.

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Run reproducible k-of-n experiments in your browser and compare adjacency and sums with exact theory.

All ten tools run locally in your browser. They describe probability models and do not predict winning numbers.