The Modern JavaScript Tutorial

Ilya Kantor has been maintaining The Modern JavaScript Tutorial for the better part of two decades — the copyright line on the site runs from 2007 — and it shows in the density. This is the closest thing the language has to a single-author textbook that is both free and current, and volunteers have translated it into more than nineteen languages.

It's structured in three parts. Part one is the language itself, part two is the browser — DOM, events, forms, interfaces — and part three collects the topics that don't fit neatly anywhere, from network requests to regular expressions.

What it covers

• The language — variables, types, operators, control flow, then objects, arrays, maps, dates and JSON
• Advanced functions — closures, decorators, binding, the parts most tutorials skip
• Prototypes and classes, explained as one subject rather than two
• Async — promises, async/await, generators, modules
• Browser work — DOM navigation, event delegation, form controls, resource loading
• Extras — Fetch, WebSockets, long polling, cookies, localStorage, IndexedDB, animations, web components, regex

Why it beats most paid courses

Depth without hand-waving. Where a video course says "closures capture the surrounding scope" and moves on, Kantor spends a chapter on lexical environments and then makes you do tasks with solutions. The exercises at the end of each chapter are the underrated part — they're small, specific, and the worked solutions explain the reasoning rather than just showing the answer.

Where it struggles

It's a wall of text and it does not care about your motivation. There's no project, no build, no thing you can show anyone at the end. The reading order is also front-loaded with fundamentals that a beginner will find dry — you're a long way in before you touch the DOM, and people quit around chapter four of part one. The EPUB and PDF versions cost money, which is fair, but it means the offline experience isn't free.

Who it's for

Anyone who has written some JavaScript and keeps hitting things they can't explain. It's also the best reference for interview preparation on language mechanics. Skip it as your very first programming resource — you want something with faster feedback, and freeCodeCamp or MDN's scripting module will keep you going longer. Skip it too if you learn by building; there's nothing to build here.

Our take

The best free JavaScript writing on the internet, and dry enough that plenty of people bounce off it. Use it as the book you keep open beside whatever project you're building rather than the thing you try to read cover to cover — that's how it actually works for most people, and treating it as a course is how it ends up abandoned at chapter six.