Document converters
YAML Frontmatter to JSON
Convert YAML frontmatter or YAML metadata into formatted JSON. Nothing you enter leaves your browser.
Your result will appear here.
What this tool does
About the YAML Frontmatter to JSON
This converter reads YAML frontmatter input and rewrites the same usable information as JSON. It changes the representation, not the meaning of the source data, except where the target format cannot express the same structure.
It helps turn structured or marked-up content into a form that is easier to publish, share, or reuse.
How to use it
- Paste YAML frontmatter in the input pane. Use the example button if you want to see the expected syntax.
- Review the input for the structure shown in the example. Then select “Convert to JSON.”
- Inspect the result for warnings or structural differences, then copy it into the destination system.
Practical example
Start with a known input
Try this sample input: --- title: Release notes draft: false --- Select “Convert to JSON” and compare the result with the source before using it elsewhere.
What to know about the result
- JSON preserves nested objects, arrays, numbers, booleans, and null values, but it requires quoted property names and does not allow comments.
- YAML uses indentation to express structure, so spacing is meaningful and tabs should not be used for indentation.
- Processing happens in this browser. Your entered text and selected files are not sent to FormatCalc for conversion.
Common questions
Using the YAML Frontmatter to JSON
Is the YAML Frontmatter to JSON free to use?
Yes. FormatCalc's YAML Frontmatter to JSON is free to use with no account required.
Is my data private when I use the YAML Frontmatter to JSON?
Yes. This tool processes your input locally in your browser. FormatCalc does not upload or store what you enter.
How do I use the YAML Frontmatter to JSON?
Paste or type your input, select any available options, and choose Convert to JSON. You can then copy the result.
What should I check before using the result?
JSON preserves nested objects, arrays, numbers, booleans, and null values, but it requires quoted property names and does not allow comments. YAML uses indentation to express structure, so spacing is meaningful and tabs should not be used for indentation. Processing happens in this browser. Your entered text and selected files are not sent to FormatCalc for conversion.