🆚 Core-js vs. Polyfill
- 📈 Polyfill is much more popular than Core-js.
- 🌍 Polyfill is more popular in all countries.
Core-js
PolyfillType
About
Core-js is a modular standard library for 
JavaScript that provides polyfills for ECMAScript up to 2024: promises, symbols, collections, iterators, typed arrays, and proposals.
Polyfill.io is an open-source JavaScript library that provides modern web API features to older browsers that do not natively support them.
It was originally owned by the Financial Times web team, then moved under community management, and after a supply chain attack in 2024 involving its cdn.polyfill.io domain, the service was discontinued and is now safely mirrored and maintained by 
Cloudflare and 
Fastly.
Headquarters
Pricing
Categories
Popularity
Determined by the number of sites using each technology.
Market share
Popularity by country
Determined by the number of sites detected from each country.
Awards
- ⬆️ 30th most popular in Israel in the JavaScript Libraries category.
- ⬆️ 36th most popular in the Philippines in the JavaScript Libraries category.
- ⬆️ 37th most popular in Hong Kong in the JavaScript Libraries category.
- ⬆️ 38th most popular in Brazil in the JavaScript Libraries category.
- ⬆️ 38th most popular in Mexico in the JavaScript Libraries category.
- 🥈 Second most popular in Russia in the JavaScript Libraries category.
- 🥈 Second most popular in Belarus in the JavaScript Libraries category.
- 🥉 Third most popular in Switzerland in the JavaScript Libraries category.
- 🥉 Third most popular in Kazakhstan in the JavaScript Libraries category.
- ⭐ 4th most popular in the United Kingdom in the JavaScript Libraries category.
Popularity by domain category
Determined by the number of sites in each category.
Top sites
Top-ranked sites that use these technologies.
Compare alternatives
Technologies with similar characteristics.
🗃️ About This Data
- We evaluate the popularity of technologies based on the number of websites where we detect their usage.
- Technologies without a detectable web footprint, and those we do not track, are not reflected in the calculated market share.
- This report is based on the analysis of 3,814,833 websites.
- Statistics were last calculated on .
- For more details, see our methodology and disclaimer.