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CSV
JSON

CSV to JSON Converter

Convert a CSV file to JSON in your browser - perfect for piping spreadsheets into scripts, APIs, or LLMs.

Why convert CSV to JSON?

CSV is the lowest-common-denominator format for tabular data: every spreadsheet exports it, every script ingests it. JSON is the same for nested or self-describing data: every programming language can parse it, every modern API consumes it. Converting CSV to JSON bridges the gap when you need to feed spreadsheet data into a JavaScript script, REST API, or an LLM that thinks in objects.

We parse the CSV with PapaParse, treating the first row as field names and the rest as records. Numeric values are auto-typed; everything else stays as strings. The output is an indented JSON array of objects - ready to paste into a script or pipe into curl. Everything happens locally; no data leaves your browser.

CSV

About CSV

CSV (Comma-Separated Values) is the simplest tabular format - plain text rows of comma-delimited values. Read by every spreadsheet program, scripting language, and data tool ever made.

JSON

About JSON

JSON (JavaScript Object Notation) is the lingua franca of structured data on the web. Arrays, objects, strings, numbers, booleans. Read by every modern programming language.

How to convert CSV to JSON

  1. 01

    Drop your CSV file

    Drag a CSV onto the converter above, or click the box to pick one from your device.

  2. 02

    JSON is already selected

    We've preselected JSON as the output format. Change it from the dropdown if you want a different target.

  3. 03

    Convert and download

    Click Convert and wait for the progress bar to finish. Download the JSON when it's ready.

CSV to JSON FAQ

See all formats →