What does this line
actually do?

Highlight a line of code, a stack trace or a config file — on GitHub, in the docs, in your editor — and Explayn explains what it does and why, in a few lines.

MacWindowsChromeiPhone & iPad

Try it here.

Highlight the whole line, or just “[{ id }]”. Then highlight a word in the answer to go deeper.

src/hooks/useUser.ts

useEffect(() => { fetchUser(id).then(setUser); }, [{ id }]);

In plain words

What the line does, what would go wrong, and the fix — not a lecture on the language.

Errors and logs

Highlight a stack trace or a log line and ask what caused it.

Any editor

On a Mac or Windows PC Explayn works in VS Code, Xcode, a terminal — any app.

Questions

Which languages?

Any language and any config format a person writes.

Is my code kept?

Only what you highlight is sent, and only to answer you; Explayn doesn’t keep it.

How much does it cost?

Nothing. Explayn is free, with no account.

Explayn is also for

students · medical words · contracts and legal wording · English learners · PDFs · YouTube · research papers · dyslexia · teachers