YAML ⇄ JSON Converter
Convert YAML to JSON and JSON back to YAML, both directions, with clear error messages — 100% in your browser, no upload.
Multiple YAML documents separated by --- are combined into a JSON array.
{
"name": "Nifty",
"tags": [
"free",
"private"
],
"nested": {
"count": 3
}
}🔒 Converted in your browser — nothing is uploaded.
Convert both directions
Paste YAML to get clean, pretty-printed JSON, or switch direction to turn JSON into YAML. The Swap button feeds the current output back in as the new input, so you can round-trip a document and compare formats. Parsing is done by the well-tested js-yaml engine, so anchors, nested mappings, sequences and multiline scalars are handled correctly rather than by a fragile hand-written parser. If your input has a syntax error, the exact message and location are shown so you can fix it.
Why convert between YAML and JSON
YAML and JSON describe the same kinds of data — objects, arrays, strings, numbers and booleans — but YAML is easier for humans to read and write (config files, CI pipelines, Kubernetes manifests) while JSON is what most APIs and programs expect. Converting lets you author in whichever format is comfortable and hand off in whichever the tool on the other side needs. Everything runs locally in your browser, so even secrets in a config file never leave your device.
Frequently asked questions
Does the conversion work both ways?
Yes. Choose YAML → JSON or JSON → YAML, or use the Swap button to turn the output back into input in the opposite direction for a quick round-trip.
What happens if my YAML or JSON is invalid?
The tool shows the parser's error message instead of a result, so you can see what went wrong — an unclosed bracket, bad indentation or a stray character — and fix it.
Is my data uploaded anywhere?
No. Parsing and conversion run entirely in your browser with JavaScript. Nothing you paste is sent to a server or stored, so it is safe for config files that contain secrets.