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Data Converter

Convert between JSON, YAML and CSV. Everything stays in your browser.

How Data Converter works

Data Converter transforms structured data between JSON, YAML, and CSV formats directly in your browser. Paste JSON and get equivalent YAML or a flat CSV; paste YAML and get JSON or CSV; paste CSV and get a JSON array of objects. The conversion logic runs locally; nothing you type or paste is sent to any server.

Each format has its strengths. JSON is the universal API interchange format. YAML is easier to read for humans and common in configuration files (Docker Compose, Kubernetes, CI pipelines). CSV is the standard for spreadsheet import/export and tabular data exchange. Having a single converter that moves between all three saves the round-trip of opening multiple tools.

Written by Bastien Sulyan

How to use Data Converter, step by step

  1. Paste your source data into the input area.
  2. Select the input format (JSON, YAML, or CSV) from the dropdown if it is not auto-detected.
  3. Select the target output format.
  4. The converted data appears in the output area.
  5. Click the copy button to copy the result to your clipboard.
  6. Set the JSON indentation if you are producing JSON. The CSV side is fixed to the comma of RFC 4180.

Common use cases

  • A DevOps engineer copies a JSON config from an API response and converts it to YAML to paste into a Kubernetes manifest.
  • A data analyst exports a JSON array from a REST API and converts it to CSV to open in a spreadsheet application.
  • A developer receives a YAML configuration file and needs its JSON equivalent to pass to a TypeScript config parser.
  • A content manager converts a CSV table of records to a JSON array to load into a CMS API endpoint via a script.

Frequently asked questions

Is the data I paste sent to any external service for conversion?

No. The conversion uses JavaScript libraries that run entirely in the browser tab. Nothing you paste here is transmitted. This is particularly relevant for converting configuration files that may contain internal hostnames, credentials placeholders, or infrastructure topology.

What are the limitations of converting JSON to CSV?

JSON can represent nested objects and arrays, while CSV is inherently flat. The converter handles an array of flat objects well: each object becomes a row and each key becomes a column header. A nested object is not serialized back to JSON in its cell: it is stringified as a plain value, which for an object gives the literal text [object Object]. Flatten your data before converting if the nested part matters. The delimiter is the comma, and cannot be changed.

Does the converter handle YAML anchors and aliases?

YAML anchors (&) and aliases (*) are a way to reuse values within a YAML document. The converter resolves anchors when parsing YAML to JSON or CSV, producing the fully expanded output. The anchor syntax itself is not preserved in the output.

Can I convert between JSON and YAML without losing comments?

YAML supports comments (lines starting with #); JSON does not. When converting YAML to JSON, comments are stripped because JSON has no comment syntax. Converting JSON to YAML will not add comments; it produces clean YAML from the data values only.

Does this tool work offline after the page has loaded?

Yes. The conversion libraries are bundled with the page. Once loaded, you can disconnect from the network and continue converting data without interruption.