Converters

CSV to JSON Converter

Convert CSV to JSON with automatic delimiter detection, quoted field support, and type inference for numbers and booleans. Copy or download the result.

Auto Delimiter
Quoted Fields
Type Inference
Copy JSON
Browser-only

Delimiter

Options

First row = headers

Auto-type values

CSV Input

Delimiter is auto-detected by default

JSON output will appear here

CSV to JSON conversion

CSV is convenient for spreadsheets and exports; JSON is convenient for APIs, JavaScript, and document databases. This converter turns each data row into an object keyed by the header row.

Options

Auto-detect comma, semicolon, tab, or pipe delimiters.
Treat first row as property names or generate col1, col2, and so on.
Infer numbers, booleans, and empty values.
Preserve quoted fields containing delimiters.

const records = [{ name: "Alice", age: 30 }];
JSON.stringify(records, null, 2);

import csv, json
json.dumps(list(csv.DictReader(open("people.csv"))))

Input	JSON value
`42`	Number
`true`	Boolean
empty cell	`null`
other text	String

Frequently Asked Questions

Does the tool auto-detect headers?: Yes — by default the first row is treated as headers and becomes the JSON object keys. You can disable this to produce arrays of arrays instead.
What delimiters are supported?: The tool auto-detects comma, semicolon, tab, and pipe delimiters. You can also manually select a delimiter.
How are numbers and booleans handled?: With auto-type detection enabled, numeric strings are converted to numbers and 'true'/'false' strings to booleans. Disable this to keep all values as strings.
What is the maximum file size?: There is no hard limit — all processing runs in your browser. Very large files (100MB+) may be slow depending on your device.
Why should CSV headers be unique?: Use unique header names so each value maps to one unambiguous JSON property.
What should I check after converting irregular CSV data?: Review the output when rows have different numbers of cells or when the CSV uses application-specific escaping, and validate it against your expected data structure.

Disclaimer

This tool is provided for general informational and utility purposes only. Results may be inaccurate, incomplete, outdated, or contain errors. Always verify results before relying on or using them.

Some tools may use AI, automated processing, third-party services, or server-side processing. Do not rely on these tools as a substitute for professional advice.

Use at your own risk. BestToolOnline makes no guarantees regarding the accuracy, reliability, completeness, availability, or suitability of results, to the maximum extent permitted by applicable law.

See our Terms of Service and Privacy Policy for complete details.

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CSV to JSON conversion

CSV is convenient for spreadsheets and exports; JSON is convenient for APIs, JavaScript, and document databases. This converter turns each data row into an object keyed by the header row.

Options

Auto-detect comma, semicolon, tab, or pipe delimiters.

Treat first row as property names or generate col1, col2, and so on.

Infer numbers, booleans, and empty values.

Preserve quoted fields containing delimiters.

const records = [{ name: "Alice", age: 30 }]; JSON.stringify(records, null, 2);

import csv, json json.dumps(list(csv.DictReader(open("people.csv"))))

Input

JSON value

42

Number

true

Boolean

empty cell

null

other text

String

Frequently Asked Questions

Does the tool auto-detect headers?

Yes — by default the first row is treated as headers and becomes the JSON object keys. You can disable this to produce arrays of arrays instead.

What delimiters are supported?

The tool auto-detects comma, semicolon, tab, and pipe delimiters. You can also manually select a delimiter.

How are numbers and booleans handled?

With auto-type detection enabled, numeric strings are converted to numbers and 'true'/'false' strings to booleans. Disable this to keep all values as strings.

What is the maximum file size?

There is no hard limit — all processing runs in your browser. Very large files (100MB+) may be slow depending on your device.

Why should CSV headers be unique?

Use unique header names so each value maps to one unambiguous JSON property.

What should I check after converting irregular CSV data?

Review the output when rows have different numbers of cells or when the CSV uses application-specific escaping, and validate it against your expected data structure.

Disclaimer

Some tools may use AI, automated processing, third-party services, or server-side processing. Do not rely on these tools as a substitute for professional advice.