Excel / CSV to JSON

Drop an Excel or CSV file and get clean JSON instantly. Headers auto-detected, types inferred, multiple sheets supported. Nothing leaves your browser.

Drop an Excel or CSV file, or click to choose

.xlsx, .xls, .csv · up to 25 MB

What This Tool Does

Spreadsheet-to-JSON is one of the most common data-wrangling tasks: you get a CSV export or an Excel report, and you need it as JSON to feed an API, seed a database, or load into a script. This tool runs entirely in your browser so your data never gets uploaded to a server.

How It Works

  • Upload an .xlsx, .xls, or .csv file (drag & drop or click).
  • The first row is treated as the header. Each following row becomes one JSON object.
  • For multi-sheet Excel files, pick the sheet from the selector.
  • Numbers and dates are detected and converted automatically.
  • Copy the JSON or download as a .json file.

Output Options

  • Pretty or minified formatting
  • Array output (default) or one object per line (NDJSON)
  • Empty cells as null or empty string
  • Automatic type detection — numbers, booleans, ISO dates
  • Key formatting — original, camelCase, snake_case, or kebab-case

Common Use Cases

  • Seed a database from an export
  • Feed a script or REST API
  • Compare two spreadsheets as structured data
  • Generate test fixtures
  • Prototype dashboards or charts from a CSV

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