Syntax Highlight

Highlight source code online

This syntax highlighter applies language-aware colors to source code so keywords, strings, comments, numbers, and markup are easier to distinguish. Select the language and visual style, then view the rendered result directly in the browser.

Highlighting changes presentation only. It does not execute, compile, lint, format, validate, or test the supplied code.

How to highlight code

1. Paste source code into the input editor.
2. Select the matching programming or markup language.
3. Choose a color theme.
4. Click Highlight and review the rendered output.

Choose the exact language when possible because similar syntax can be tokenized differently. Plain text or an incorrect language may produce fewer or misleading colors without changing the underlying code.

Syntax highlighting limitations

A highlighter recognizes lexical patterns rather than fully understanding program behavior. Valid-looking colors do not mean the code is syntactically correct, secure, or compatible with a particular compiler version.

Never rely on highlighting to review untrusted code for malicious behavior. Use the language’s parser, compiler, linter, tests, and security tools for those tasks.

Syntax highlight FAQ

Does this tool modify the source code?

No. It renders a highlighted view while preserving the source text used as input.

Why is part of my code colored incorrectly?

The selected language may be wrong, the grammar may not support a newer feature, or malformed syntax earlier in the file may affect later tokenization.

Can highlighted code be executed here?

No. This is a presentation tool and does not run the input, which also reduces the risk of accidentally executing pasted code.