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Data / LOCAL TOOL

JSON, YAML & CSV Converter

Convert JSON, YAML, and CSV locally with inferred input and explicit output format.

Runs locally — input is never uploaded
Paste or drop JSON, YAML, or CSV
Ready when you are

WHAT IT DOES

Move structured data between the formats you use.

Paste or drop JSON, YAML, or CSV, choose the output format, and convert locally. JSON is tried first because it is also valid YAML, while CSV is recognized only when its rows and columns give strong evidence that it is tabular data. Nested objects flatten to dotted CSV headers, arrays and objects become JSON cells, and heterogeneous records use the first-seen union of their columns.

Why use it?

Use it to move structured records between configuration files, API payloads, and tabular workflows. A table cannot preserve every nested structure as native columns.

How to use this tool

  1. Paste or drop the source and choose the required output format and, for CSV, delimiter.
  2. Convert and check the reported input interpretation, column names, and quoting.
  3. Try two records with different keys to see how missing cells are represented. Review dotted headers and JSON-valued cells before treating a CSV round trip as the original nested document.

Details and limitations

  • CSV delimiter detection considers comma, semicolon, tab, and pipe, while the output picker lets you choose the delimiter explicitly.
  • CSV headers must be non-empty and unique, and quoted fields support delimiters, line breaks, and escaped double quotes.
  • JSON and YAML arrays of objects become rows; nested objects flatten with dotted paths and arrays or objects are JSON-stringified inside cells.
  • YAML parsing follows the existing YAML 1.2 core behavior, including streams and explicit errors for values JSON cannot represent.

COMMON QUESTIONS

JSON ↔ YAML ↔ CSV questions

How does the converter decide what I pasted?
It tries JSON first, then looks for strong tabular CSV evidence with consistent rows and at least two columns, and finally tries YAML. This order matters because every JSON document is valid YAML.
How are nested values represented in CSV?
Nested objects become dotted headers such as user.name. Arrays and objects that are not flattened are written as JSON text inside one quoted CSV cell, so their structure is not silently discarded.
Can I choose a semicolon or tab delimiter?
Yes. CSV output supports comma, semicolon, tab, and pipe. Input detection examines those same delimiters and uses the strongest consistent table shape.
Can I choose the output format?
Yes. The output picker supports JSON, YAML, and CSV. CSV output also lets you choose comma, semicolon, tab, or pipe delimiters; input format is still inferred locally so the tool does not ask you to identify something it can read itself.