APIs & data handoff

CSV to JSON Converter

Turn a CSV file into a JSON array, with a real quoted-field parser and a preview of how every column will be typed.

Round-trip verified

Output rules

Delimiter

Quote character

Nested keys

Arrays

Array separator

null is written as

Line ending

HandlingFirst row is a headerWrite a UTF-8 BOMQuote every fieldRead numbers and booleans as types

Paste CSV or open a .csv file to convert.

How each column will be read

Convert something to see the column list.

Round-trip verification

Converts the JSON to CSV and straight back with the same rules, then compares the result value by value. Anything CSV cannot represent shows up here rather than three weeks later in production.

Files are read into this browser tab only — there is no upload endpoint and no payload in the URL. See how local processing works.

How to Convert CSV to JSON

Paste your CSV data with headers in the first row. Click Convert and each row becomes a JSON object with header names as keys.

What is CSV?

CSV is a simple text format for tabular data. Each line represents a row, with values separated by commas. It's the standard export format for spreadsheets and databases.

What is JSON?

JSON is a structured data format ideal for APIs and programming. Converting CSV to JSON makes spreadsheet data easy to use in web applications.

Common Use Cases

Convert CSV to JSON when importing spreadsheet data into web apps, processing exported database data, or preparing data for REST APIs.

Convert CSV to JSON in Code

When the conversion needs to run in a script or pipeline:

Python (pandas)

import pandas as pd
pd.read_csv("data.csv").to_json("data.json", orient="records", indent=2)

Python (stdlib)

import csv, json
with open("data.csv") as f:
    print(json.dumps(list(csv.DictReader(f)), indent=2))

Node.js

const [header, ...lines] = require("fs").readFileSync("data.csv", "utf8").trim().split("\n");
const keys = header.split(",");
const json = lines.map(l => Object.fromEntries(l.split(",").map((v, i) => [keys[i], v])));

Frequently Asked Questions

Does the first row need to be headers?

Yes, by default the first row is treated as column headers which become the JSON object keys.

What delimiter formats are supported?

The converter auto-detects common delimiters including comma, semicolon, and tab characters.

How are empty values handled?

Empty values are converted to empty strings in the JSON output. You can optionally treat them as null.

Can I convert TSV (tab-separated) files?

Yes, the converter automatically detects tab-separated values and processes them correctly.

APIs & data workflow

Continue with the data, not the directory

Prepare CSV, XML, tables, SQL, and DynamoDB payloads for the next system in the workflow.

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