YAML JSON Converter - Online YAML to JSON / JSON to YAML

1. YAML ↔ JSON

The default sample already mixes maps and lists — run it once, then swap in your own file. Structure is preserved, but YAML comments disappear in JSON. That is a format limit, not a missing feature.

1. YAML → JSON: paste YAML on the left, convert, and read equivalent JSON on the right.
2. JSON → YAML: paste JSON and convert back to indented YAML.
3. On failure, read the hints: mixed indent, missing space after colons, list dash placement, and more.

2. YAML traps that catch everyone

On the JSON side, trailing commas, single quotes, and raw newlines are the usual breakers. Fix JSON in the formatter first, then convert to YAML.

• Tabs mixed with spaces: YAML forbids tab indent; the editor can look aligned and still fail.
• Space after colon is required: key:value is illegal; key: value is legal.
• List dashes and nesting depth: children must sit one level deeper than parents.
• Unquoted specials: strings with colons, #, or braces are safer inside quotes.

3. Where it fits

Next: use JSON Diff when structures must align; use JSON→TypeScript / Go / Java when you need types. This page only swaps formats — business schema checks belong in the JSON Schema validator.

• Turn docker-compose / GitHub Actions YAML into JSON for JSON-only toolchains.
• Turn API JSON into YAML for human-readable design docs.
• Normalize two "identical looking" configs to one format before diffing.

4. Large integers and precision edges

JSON numbers in the browser follow IEEE-754: integers beyond 2^53-1 lose precision. On the JSON→YAML path this page tries to keep oversized integers as strings; YAML→JSON is still limited by the parser's number type — quote order IDs and snowflake IDs as strings at the source. A successful convert is not the same as a lossless round-trip: lost precision often shows up in diffs as "the number just changed".

5. Multi-docs and anchors this page does not cover

• --- separated multi-document YAML is common in Helm/K8s manifests; this page parses a single document — split first.
• Anchors and aliases (&anchor / *alias) are YAML-only reuse; JSON expands them into duplicated structures and drops the alias names.
• YAML boolean dialect forms (yes/no/on/off, ~) become true/false/null — quote them if you meant the string "yes".

6. Format-then-convert workflow

Dirty JSON (trailing commas, pseudo-JSON comments) should pass a JSON formatter/validator before this page; dirty YAML should be fixed from this page's indent hints. Once both sides are valid, review changes with text diff or JSON diff. Treat the converter as a syntax gate, not a "paste anything and ship it" button.