Polyfill Impact Checker

v1.0.0

Pick a browserslist + features → polyfill bytes added to your modern bundle.

Feature to polyfill

Browser target

Result

Polyfill Impact: Promises for last2

Polyfill needed: none — native

All targets:
  last2         none — native
  Chrome70      none — native
  iOS12         none — native
  IE11          ~2 KB (core-js/es.promise)

Recommendation: use core-js@3 with useBuiltIns: "usage" in babel-preset-env
to automatically include only what each target actually needs.