ToolPad
Runs locally in your browser. Nothing you paste is sent to a server.

CSV → JSON

Convert CSV to JSON instantly. Runs locally in your browser.

Runs locally in your browser. Nothing you paste is sent to a server.

CSV (Input)

0 chars · 1 lines · Size: 0 B
1

JSON (Output)

Tip: You can verify in DevTools → Network that nothing is uploaded.

CSV to JSON options

Characters
Use \t for tab
Leave empty to disable
Converting
Dynamic types: converts true/false/null/numbers automatically
Indentation

About this CSV to JSON Converter

Use this tool to convert CSV data to JSON format. Supports custom delimiters, quote characters, headers, and type conversion. Everything runs locally in your browser — nothing you paste is sent to a server.

Features
  • Custom column separators (comma, tab, etc.)
  • Header row support with automatic object conversion
  • Dynamic type conversion (numbers, booleans, null)
  • Skip comment lines and empty rows
Tips
  • Enable Auto to convert as you type
  • Use headers for object-based JSON output
  • Dynamic types automatically convert values
  • Invalid CSV will show an error message

FAQ

Is my CSV data uploaded to a server?

No. Conversion happens locally in your browser. Nothing you paste is sent to a server.

How does dynamic types work?

When enabled, the converter attempts to parse values as booleans (true/false), null, or numbers. Values that don't match these patterns remain as strings.

What happens with duplicate headers?

Duplicate headers are automatically made unique by appending _2, _3, etc. to the header name.

Can I use tab-separated values (TSV)?

Yes. Enter \t in the column separator field to use tabs.

What if my CSV has inconsistent columns?

The converter validates that all rows have the same number of columns. If they don't match, an error will be shown.

Can I upload large CSV files?

Yes, but extremely large files may be slow depending on your device. The current limit is 5MB.