Polyfill is a service which accepts a request for a set of browser features and returns only the polyfills that are needed by the requesting browser.
Moment JS is leading in Top 100K Sites, Top 1M Sites and The Entire Web.
Polyfill.io is leading in Top 10K Sites.
Moment JS has better usage coverage in more websites categories. Including Science & Education, Computers Electronics & Technology, Arts & Entertainment, Travel & Tourism and 20 other categories.
Polyfill.io hasn't got a lead over Moment JS in any websites category.
Moment JS is leading in most countries, including Russia, Germany, France, South Korea and 126 other countries.
Polyfill.io is leading in United States, United Kingdom, Canada, Japan and 32 other countries.