ToolBirch

CSV to JSON

Convert CSV rows into a JSON array with optional type inference.File & Data Tools

CSV to JSON

Convert CSV rows into a JSON array of objects, with optional type inference for numbers and booleans.

About this tool

Rows become objects keyed by the header row. With type inference on, values that look like numbers or true/false are emitted as real JSON types instead of strings.

How to use the CSV to JSON tool

  1. Paste or drop the CSV. The header row provides the object keys.
  2. Choose inference. Numbers and booleans become native JSON types, or stay strings.
  3. Copy the JSON. Formatted with two-space indentation.

Supported formats

Input

  • Plain text or file input

Output

  • Converted or analysed output

Inputs are validated before anything is processed. Invalid values and unsupported files are rejected with a clear error instead of failing silently.

Frequently asked questions

How is inference decided?

Strict patterns: optional minus, digits, optional decimal part; plus exact true/false. Ambiguous values stay strings.

What about duplicate headers?

Later columns overwrite earlier ones in the object.

Are empty cells included?

Yes, as null under inference or as empty strings without it.

Privacy

Everything you enter stays in this browser tab. There is no upload endpoint for tool inputs, no account, and no server-side copy of your text or files. Results are produced locally and disappear when you close the page.

No account is required and no file is ever uploaded. See the privacy policy for details about analytics and the limited data this site stores.

Known limitations

  • Nested structures are not expressible in flat CSV, so none are produced.

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