YAML to JSON Converter
Convert between data formats instantly with this yaml to json converter. Transform your data for different applications and programming languages.
Features
- Instant Conversion: Transform data formats in milliseconds
- Preserve Structure: Maintains data relationships and hierarchy
- Error Handling: Clear feedback on conversion issues
- Copy Output: One-click copying of converted data
Example
Input:
``
server:
host: localhost
port: 3000
`
Output:
`
{"server": {"host": "localhost", "port": 3000}}
`
Tips
Indentation must be consistent- Comments are stripped during conversion
- Anchors and aliases are resolved
How to Use
1. Paste your source data in the input area
2. Click convert to transform the data
3. Review the converted output
4. Copy or download the result
Best Practices
- Validate your source data before conversion
- Check the output for any formatting issues
- Test with a small sample before converting large files
- Keep backups of original data
YAML and JSON
YAML JSON Types Strings, numbers, booleans, null, dates, plus anchors and references string, number, boolean, null, object, array Comments Yes, with # Not allowed — a comment makes the document invalid Good at Readable, comments, references — which is why config files use it Unambiguous, parsed natively everywhere, no configuration Bad at Significant whitespace, and the Norway problem: unquoted no parses as boolean false No comments, no dates, no integers distinct from floats, verbose for humans
What Does Not Survive the Trip
YAML has types JSON lacks. Dates become strings, anchors and references are expanded (which can multiply the output size), and duplicate keys — legal in some YAML parsers — collapse.
Rules Worth Following
- Convert once, at the boundary. Round-tripping through a lossier format repeatedly
degrades the data a little each time.
- Validate after converting, not before. The conversion is where things break.
- Keep the original. The converted copy is a derivative, not a replacement.
- Watch encoding. UTF-8 without a BOM is right for everything here; Excel writes a BOM
and some parsers choke on it.Numbers Are the Recurring Problem
A JSON number is an IEEE 754 double. Three consequences that bite in production:
Twitter hit the first one publicly: 64-bit tweet IDs arrived in JavaScript rounded, so the
API began sending an Value What happens Integers above 2⁵³ Silently lose precision — send IDs as strings Money as a float 0.1 + 0.2 = 0.30000000000000004 Leading zeros 007 is invalid JSON; "007" is a stringNaN and InfinityNot valid JSON at all alongside every id.
Keys, Order and Duplicates
Objects are formally unordered, though every JavaScript engine preserves insertion order for
string keys — with one exception: integer-like keys sort numerically and come first.
`javascript
JSON.stringify({ b: 1, 2: 2, a: 3 }); // {"2":2,"b":1,"a":3}
`
Duplicate keys are not an error in the spec, and JSON.parse` keeps the last one. Two
parsers can legitimately disagree about which value wins, which has been the basis of real
request-smuggling attacks.