JSON to YAML Converter

What this converter does

JSON and YAML describe the same thing — a tree of keys, values, lists and scalars — but they write it down differently. JSON uses braces, brackets and quotes; YAML uses indentation and far less punctuation. Because the underlying data model is nearly identical, converting from one to the other is lossless in practice, and this tool does that conversion in a single pass as you type.

What you get back is not a mechanical transcription. The converter makes the output readable the way a person would write it: strings are left unquoted when quoting them would add nothing, keys that could be misread as booleans or numbers are quoted so they survive a round trip, and a string containing newlines becomes a block scalar (|) rather than one long line full of \n escapes. That last point is the single biggest reason people convert to YAML — a shell script or a certificate embedded in JSON is unreadable, and in YAML it reads like the original file.

Everything happens in the browser tab. There is no upload step, no server round trip and no request in the network panel, which matters because the JSON people convert is very often a Kubernetes secret, a CI configuration or a credentials block.

When converting JSON to YAML is the right move

The conversion is usually driven by the tool that will read the file rather than by preference:

• Kubernetes manifests. The API returns JSON, but manifests are written, reviewed and committed as YAML. Converting an object you pulled with kubectl get -o json gives you something you can actually put in a pull request.
• CI/CD pipelines. GitHub Actions, GitLab CI and CircleCI all expect YAML. A pipeline definition generated by a script or an API is usually JSON first.
• Docker Compose. Compose files are YAML, and converting from JSON is the quickest way to turn programmatic output into something you can hand-edit.
• Configuration you want to comment. JSON has no comment syntax. Moving a config to YAML is often done purely so the team can explain why a value is what it is.
• OpenAPI and AsyncAPI specs. Both formats accept either, but YAML is what most teams keep in version control because the diffs are readable.

There is one case where you should not convert: if a file is only ever read by a machine and never edited by a person, JSON's stricter grammar is an advantage. YAML's flexibility is what makes it pleasant to write and also what makes it possible to write something ambiguous.

How JSON and YAML differ in practice

The differences that actually bite when you convert between them:

One asymmetry is worth knowing about. Every valid JSON document is also valid YAML, because YAML 1.2 was deliberately defined as a superset of JSON. The reverse is not true: plenty of YAML has no JSON equivalent, including comments, anchors and multiple documents in one file. So JSON to YAML always succeeds, while YAML to JSON can legitimately fail.

The quoting traps this converter avoids

YAML's convenience comes from guessing what you meant, and the guesses occasionally go wrong. The classic example is the so-called Norway problem: in YAML 1.1, the unquoted value no parses as the boolean false, so a country list containing Norway's NO code silently becomes false. Related traps include yes, on, off, and version numbers like 1.10 which parse as the float 1.1.

This converter quotes any scalar that a parser could reinterpret — reserved words, anything that looks numeric, strings with leading or trailing whitespace, and strings starting with a character that has structural meaning. The result is slightly more quoting than a minimal encoder would emit, and output that survives a round trip through any parser without changing meaning. If you want to confirm that, run the result back through the YAML to JSON converter and compare.

How to use the JSON to YAML Converter

1. Paste or upload your JSON

   Paste into the left pane, or use Upload file to load a .json file from your machine. The file is read in the browser, not sent anywhere.

2. Pick your indentation

   Two spaces is the common default and what Kubernetes, GitHub Actions and Docker Compose examples use. Choose four if your team's style guide calls for it.

3. Check the status line

   If the JSON has a syntax error, the status bar names the line and column rather than just refusing. Fix it and the output updates as you type.

4. Copy or download the YAML

   Use Copy output for pasting into an editor, or Download to save it as a .yaml file.

Frequently asked questions