Is this a full linter?

No. It checks syntax, not style or logic. Pair with ESLint, Prettier, or your language-specific linter for deeper analysis.

Which JS version does it target?

Modern ECMAScript (the latest stable). If you use experimental syntax (stage 2 or earlier), expect false negatives.

Does the SQL checker know my dialect?

The parser is ANSI-leaning. Vendor extensions (T-SQL specifics, PL/pgSQL) may be flagged even when they would run fine.

$syntax-checker

Testers

Validate syntax for JSON, YAML, JavaScript, HTML, CSS, and SQL. Get line and column numbers for errors. Everything runs in your browser — nothing is sent to a server.

Language:

Code

How it works

Validates using the native JSON.parse() parser. Reports exact position of syntax errors.

// how-to

How to check code syntax

Quickly validate JSON, YAML, JavaScript, HTML, CSS, and SQL snippets for syntax errors.

Pick the language
Choose JSON, YAML, JavaScript, HTML, CSS, or SQL from the language selector.
Paste the code
Paste your snippet into the input area.
Run the check
The checker reports the first syntax error with line and column, or confirms a clean parse.
Fix and re-check
Edit and re-run until the parser is happy.

// faq

? Is this a full linter?: No. It checks syntax, not style or logic. Pair with ESLint, Prettier, or your language-specific linter for deeper analysis.
? Which JS version does it target?: Modern ECMAScript (the latest stable). If you use experimental syntax (stage 2 or earlier), expect false negatives.
? Does the SQL checker know my dialect?: The parser is ANSI-leaning. Vendor extensions (T-SQL specifics, PL/pgSQL) may be flagged even when they would run fine.