Validated with js-yaml (YAML 1.2) entirely in your browser — nothing is uploaded.
Validate YAML syntax online, free. YAML is an indentation-based data format favoured for human-edited configuration. This validator checks your YAML against YAML 1.2.2 and reports syntax errors with clear messages — processing runs in your browser with nothing uploaded.
It parses your YAML and pinpoints syntax errors so you can fix them before they break a build or deploy. 100% free, no registration, and complete privacy — everything runs locally in your browser, so your data never touches a server.
Find YAML syntax problems instantly, with messages that point to what needs fixing.
Validation follows YAML 1.2.2, so a pass means standards-compliant YAML.
Your YAML is parsed locally in JavaScript; nothing is uploaded, logged, or stored.
Unlimited validation with no account or quota, on desktop and mobile.
Paste your YAML into the input box and click Validate. The validator runs instantly in your browser and shows the result on the right — no upload, no signup, no installation.
Yes. The YAML validator is completely free with no limits, no account, and no watermark. All processing happens locally in your browser for privacy.
No. Your YAML never leaves your device — it is processed locally in JavaScript. We don't upload, log, or store your input, so it's safe for proprietary code and config.
It checks your YAML for syntax errors and structural validity against YAML 1.2.2, and reports clear messages pointing to anything that needs fixing.
Yes. The tool is fully responsive and works on phones, tablets, and desktops — just open it in any modern browser.