RegexLearn

regexlearn.com is a free, open-source platform that turns regular
expressions from a black art into a skill you can pick up in an afternoon. Learn step by step in 21
languages, keep the cheatsheet nearby, and test your patterns live in the playground.

Features
- Step-by-Step Learning: Interactive lessons that progress from the basics to advanced
patterns, one small step at a time. Matches light up as you type, and your progress is saved in
your browser.
- Courses: Two lesson tracks are available: Regex 101
for fundamentals and Regex for SEO for practical,
search-focused usage.
- Cheatsheet: A concise summary of regex syntax with a live example for every entry.
- Playground: A private, browser-based sandbox to write and test regex patterns. Everything
runs locally; nothing you type is sent to a server.
- Shortcut Friendly: Move through lessons, toggle flags, and reveal answers from the keyboard.
- Works Everywhere: Responsive on phones and tablets, with right-to-left support for Arabic and
Persian.
 |
 |
 |
| Learn |
Cheatsheet |
Playground |
Supported Languages
Available in 21 languages:
| 🇺🇸 English | 🇹🇷 Turkish | 🇷🇺 Russian |
| 🇪🇸 Spanish | 🇨🇳 Chinese (Simplified) | 🇹🇼 Chinese (Traditional) |
| 🇩🇪 German | 🇺🇦 Ukrainian | 🇫🇷 French |
| 🇵🇱 Polish | 🇰🇷 Korean | 🇧🇷 Brazilian Portuguese |
| 🇨🇿 Czech | 🇬🇪 Georgian | 🇮🇷 Persian |
| 🇮🇹 Italian | 🇸🇦 Arabic | 🇧🇩 Bengali |
| 🇯🇵 Japanese | 🇮🇩 Indonesian | 🇻🇳 Vietnamese |
Speak a language that isn’t listed? Adding it is a single pull request: copy the
en folder in src/localization/, translate the JSON
files, and you’ve brought regex to every developer who reads in your language. Prefer to start a
conversation first?
Open an issue.
Translation Guidelines
- English is the reference. Translate from
src/localization/en and keep
exactly the same keys in every file.
- Leave code as it is. Text between backticks (
`[a-z]`, `OK`) is rendered as code;
don’t translate it, and keep every pair of backticks.
- Keep the line breaks.
\n marks a line break inside a lesson text; keep it in the same place.
- Match the lesson. Each step asks the learner to type a specific answer, so a translated
instruction must still lead to that exact answer.
Development
Built with Next.js, React,
TypeScript, and Tailwind CSS. The
site is exported as static HTML.
Requires Node.js 20.9 or newer (the pinned version is in .node-version).
npm install # install dependencies
npm run dev # start the dev server at http://localhost:3003
npm run lint # lint the project
npm run build # static production build in out/
Local environment variables belong in .env or one of Next.js’s .env.*.local files. These files
are ignored by Git and must not contain values intended for source control.
Contributing
RegexLearn is shaped by its community: lessons, translations, and fixes in this repo came from
contributors around the world. Spotted a typo, a bug, or an awkward translation? A small pull
request is all it takes to improve the experience for thousands of learners.
- Please target the
main branch with your pull requests.
main is production: every pull request merged into it is deployed to
regexlearn.com automatically, so please make sure npm run build
passes before opening one.

RegexLearn is free for everyone, and sponsors are what keep it that way. Sponsorship puts your
brand in front of a worldwide audience of developers at the exact moment they’re learning. Want
your logo up there? Get in touch.
License
This project is licensed under the MIT License. See the LICENCE file for details.
评论