YAML to JSON Converter
Convert YAML to JSON online in your browser. Handles block scalars, flow collections, anchors and multi-document files — nothing is uploaded.
What is the YAML to JSON Converter?
The ByteTools YAML to JSON Converter turns a YAML file into clean, formatted JSON. It reads block mappings and sequences, inline flow collections, single- and double-quoted scalars, literal and folded block scalars with their chomping indicators, comments, anchors and aliases, and multiple documents separated by three dashes.
- Parses block scalars (| and >) with strip, clip and keep chomping
- Understands flow collections, anchors, aliases and ignored tags
- Multiple --- documents become a JSON array
- Errors name the exact line and column that failed
- Warns about duplicate keys instead of silently dropping them
- Runs entirely in your browser — YAML is never uploaded
How to use the YAML to JSON Converter
- 1
Paste your YAML into the input box, or drop a .yml or .yaml file onto the drop zone.
- 2
Leave 'Pretty-print with 2-space indent' ticked for readable JSON, or untick it for a compact single line.
- 3
Click Convert to JSON.
- 4
Check the document count and any warnings, then Copy the JSON or Download it as a .json file.
About the YAML to JSON Converter
The ByteTools YAML to JSON Converter turns a YAML file into clean, formatted JSON. It reads block mappings and sequences, inline flow collections, single- and double-quoted scalars, literal and folded block scalars with their chomping indicators, comments, anchors and aliases, and multiple documents separated by three dashes.
It is built for developers who live in CI pipelines, Kubernetes manifests, Docker Compose files and OpenAPI specs, and who need the same data as JSON to feed a script, an API client or a test fixture. Errors report the exact line and column, so a broken file tells you where it broke instead of just failing.
Everything runs 100% locally in your browser with JavaScript. Your YAML is never uploaded, logged or stored, which makes the tool safe for production manifests, internal service configuration and anything containing infrastructure detail you would rather keep off a server.
Frequently asked questions
How do I convert a YAML file to JSON?
Paste the YAML or drop the .yml file into the input box and click Convert to JSON. The converted JSON appears below with a copy button and a download link, and the whole conversion happens inside your browser.
Why did my value 0755 become the number 493?
YAML 1.1 treats a leading zero followed by digits as an octal integer, so 0755 resolves to 493 in decimal. If you want it to stay text, quote it in the YAML as "0755" and the converter will keep it a string.
What happens to YAML dates, .inf and .nan?
JSON has no date type and cannot represent infinity or not-a-number, so those values are emitted as strings. That keeps the output strictly valid JSON that JSON.parse and every JSON library will accept.
Does it support multiple YAML documents in one file?
Yes. Documents separated by --- are each parsed and returned together as a JSON array, and the document count is shown above the output so you can confirm how many were found.
Is my YAML sent to a server?
No. Parsing runs entirely in your browser with JavaScript, so nothing is transmitted or stored. That makes the tool safe for Kubernetes manifests, CI secrets files and other private configuration.
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