Developer Tools

JSON ↔ CSV ↔ YAML Converter

Convert between JSON, CSV, and YAML instantly — runs entirely in your browser. Nothing is uploaded to any server.

Format:

Paste or type your data above. Conversion happens automatically.

Format:

CSV output requires an array of flat objects (each row = one object).

All conversion happens locally in your browser. No data is sent to any server.

Overview

JSON, CSV & YAML Converter: instant data format conversion in your browser

This converter lets you switch between the three most common structured-data formats — JSON, CSV, and YAML — with a single click. Paste your data into the input panel, pick the source format and the target format, and the converted output appears immediately. You can copy it to the clipboard or download it as a file.

The entire conversion runs in your browser using JavaScript. Your data never leaves your device and is never sent to any server. It is completely free with no account, no rate limits, and no tracking.

100% freeNo sign-upRuns in your browserNothing uploaded
How to use the converter
  1. 1Paste your JSON, CSV, or YAML data into the input textarea on the left.
  2. 2Select the correct input format from the dropdown (JSON, CSV, or YAML).
  3. 3Choose the output format you want on the right panel.
  4. 4The converted result appears instantly. Use the Copy button to copy it to your clipboard, or Download to save it as a file.
  5. 5If there is a parse error (e.g. malformed JSON or invalid YAML), a clear error message is shown in the output panel.
Key features
  • Converts in all six directions: JSON ↔ CSV, JSON ↔ YAML, and CSV ↔ YAML
  • Auto-converts as you type — no need to click a Convert button
  • Quick-switch buttons for every direction (JSON → CSV, YAML → JSON, etc.)
  • YAML powered by js-yaml (the industry-standard library used in Node.js tooling)
  • CSV parser handles quoted fields, embedded commas, and escaped double-quotes
  • One-click Copy to clipboard and Download as .json / .csv / .yaml
  • Clear error messages when input is malformed or incompatible with CSV
  • 100% client-side — your data never leaves your browser

Frequently asked questions

Is this converter free?
Yes, completely free. There is no cost, no account required, and no usage limits. It runs entirely in your browser.
Is my data uploaded to a server?
No. All conversion logic runs locally in your browser using JavaScript. Your data is never sent to any server, logged, or stored anywhere outside your own device.
Why does CSV conversion fail for some JSON?
CSV is a flat tabular format — it can only represent an array of flat objects where each object has the same set of keys. Nested objects, arrays-of-arrays, and single root objects cannot be expressed as CSV rows. If your data has a shape that cannot fit in a table, the converter will explain this with an error message. Converting to JSON or YAML always works regardless of the data shape.
What YAML version and library does this use?
The converter uses js-yaml v4, the most widely adopted JavaScript YAML library (used by Webpack, ESLint, and many other tools). It parses and emits YAML 1.2 compatible output.

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