Bundle Size Estimator

Enter npm package names, estimate their gzipped sizes, and see the cumulative impact on load time.

Add a package

Selected packages

Cumulative impact

Estimated load time by connection speed

Tip: Sizes come from a curated reference table of common package gzip sizes — for packages not in the table, type an estimated KB size manually when prompted. This won't hit a live registry, so treat numbers as ballpark estimates for comparing options, not exact byte counts.