CSV to JSON

Convert CSV into JSON while preserving IDs and leading zeros as text. Keep your data on your device.

CSV input

Local processing · UTF-8 files · input up to 1 MiB · up to 20,000 lines or CSV records. Nothing you enter is uploaded.

OptionsFirst record contains column namesTrim cell whitespaceDelimiter

Result

Your result will appear here after processing.

How do I convert CSV to JSON?

Paste CSV or choose a UTF-8 CSV file, select comma, semicolon or tab, then choose Convert to JSON. Copy or download the result. Empty records are skipped.

How are headers and values handled?

With First record contains column names enabled, each data record becomes an object. Column names must be unique and nonempty. Without headers, records become arrays. All cell values remain strings, preserving leading zeroes and long numbers.

Keep leading zeros and long IDs

Input

code,id
001,9007199254740993

Output

[
  {
    "code": "001",
    "id": "9007199254740993"
  }
]

Are quotes and multiline fields supported?

Quoted fields may contain delimiters and line breaks. Use two double quotes to represent one quote. Every record must have the same number of fields. Unexpected quotes, text after a closing quote and unclosed fields are rejected.

Convert quoted commas and multiline cells

Input

name,note
Hazel,"Hello, world"
Oak,"line one
line two"

Output

[
  {
    "name": "Hazel",
    "note": "Hello, world"
  },
  {
    "name": "Oak",
    "note": "line one\nline two"
  }
]

What can I do next?

Copy your result before opening another tool, then paste it there.

Format and inspect JSON to explore the converted rows in a tree.
Convert JSON back to CSV when you need a delimited file.

What are the limits?

Input is limited to 1 MiB and 20,000 records including the header; JSON output is limited to 4 MiB. This tool converts structure without interpreting dates or numbers. Input and results are cleared when you leave or reload.