JavaScript practice challenges

Public JavaScript challenges shared by the EraCode community. These pages are teasers — skill maintenance starts when you attempt the full problem inside EraCode.

Daily JS: Count Items with a Map

beginnerMulti-PartJavaScript

Quick practice on JavaScript data structures: using Map for frequency counting, plus a short concept check.

Other technologies

All challenges C Cloudflare Django Django REST Framework Docker Express Flask Git LIBOR Next.js PostgreSQL Python R SQL Sequelize Sushiswap Tailwind CSS Third-party APIs TypeScript Zod