Bootstrap Resampling Visualizer
The bootstrap estimates how uncertain a statistic is by resampling the data you already have. This tool takes a sample, draws thousands of bootstrap samples from it with replacement, recomputes the chosen statistic (mean or median) on each, and builds up the bootstrap distribution. The 2.5th and 97.5th percentiles give a 95% confidence interval without any formula or normal assumption — you can watch the interval settle as the resamples accumulate.
Runs 100% in your browser — simulations are computed locally on your device.
Read the full guide to this tool
Notes
- Each bootstrap sample is the same size as the original, drawn with replacement, so some points repeat and others are left out.
- The spread of the bootstrap statistics estimates the standard error; the middle 95% gives a percentile confidence interval.
- The bootstrap needs no distributional assumption, which is why it works for awkward statistics like the median.
- Runs 100% in your browser — simulations are computed locally on your device.
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