JSON / YAML Formatter — Engineering
Format, beautify, and convert between JSON, YAML, and JavaScript — turn a JSON payload into YAML and back, or clean up a hand-written JS object. Auto-detects the input format. Private, in-browser, no account.
How it works
- Paste JSON, YAML, or a JavaScript object — the format is detected automatically.
- Click JSON, YAML, or JavaScript to beautify and convert the content in place.
- Copy the result. Everything runs in your browser — nothing is uploaded.
Key features
- Auto-detects JSON, YAML, and JavaScript object literals
- Beautify and convert between all three formats in one field
- Distinguishes valid JavaScript ({ x: 2 }) from strict JSON ({ "x": 2 })
- Invalid input is flagged, never silently converted
- Free, private, no account required
Common uses
- Convert a JSON config into readable YAML, or the reverse
- Turn a hand-written JavaScript object into valid JSON
- Beautify a minified payload to inspect it
- Normalize a file's formatting before diffing two versions
Frequently asked questions
How do I compare json / yaml formatter online?
Paste JSON, YAML, or a JavaScript object — the format is detected automatically. Click JSON, YAML, or JavaScript to beautify and convert the content in place. Copy the result. Everything runs in your browser — nothing is uploaded.
Are my files private when I use this tool?
Yes. All comparison runs locally in your browser. Your files never leave your device and are never sent to any server — not a policy promise, but an architectural fact. There is no server receiving your data.
No AI means no hallucinations
Compare Files uses a deterministic, logic-based engine — not a language model. It reports every change that is actually in your files, and never invents one.
Your files never leave your device. Everything runs in your browser — no uploads, nothing stored.
No AI, so no hallucinations. A deterministic engine reports every real change and never invents one.
No upload, no server wait. Comparisons run locally and keep working offline once the page has loaded.