Convert CSV to JSON

Transform simple CSV text files into structured JSON for APIs and apps.

4.9/5 - 1,450 votes

Drag & Drop CSV files here

or click to browse from your device

How to Convert CSV to JSON?

Turn comma-separated values into a structured JSON array for your applications.

Upload CSV

Drag & drop your .csv file. Make sure the first row contains your headers.

Parse & Map

We map each column to its header key and convert rows into objects.

Download JSON

Get a single .json file containing an array of your data.

Developer Tip

JSON is lighter than JavaScript Object Notation and natively supported by JavaScript. Converting legacy CSV data to JSON makes it instantly usable in modern web apps.

Behind the Code

Parsing Text to Structured Objects

Converting CSV to JSON involves more than just swapping delimiters. It requires mapping headers to keys and validating data types.

Our engine reads the first row as Keys. It then iterates through every subsequent row, creating an Object for each, and populating it with values. We handle escaping quotes, special characters, and UTF-8 encoding automatically.

The output is a lightweight, minified JSON array ready for your REST APIs or NoSQL databases.

From Rows to Objects

CSV is a flat format, representing data in rows and columns. JSON is a hierarchical format, representing data as objects and arrays.

Our CSV to JSON tool bridges this gap. It takes the rigid structure of a spreadsheet and transforms it into the flexible, key-value structure of JSON, perfect for NoSQL databases like MongoDB or for feeding frontend components.

CSV vs. JSON

Feature

CSV (.csv)

JSON (.json)

Structure

Flat (2D Grid)

Nested (Tree)

Readability

Human readable

Machine readable

Web Use

Downloadable Reports

APIs & Data Transfer

Size

Compact

Verbose (Repeats Keys)

Key Terminology

Array []

Top level container. Your CSV becomes one big Array containing many Objects.

Object {}

Represents one row from your CSV. Contains keys (headers) and values (cells).

Key

The name of the property, taken from the CSV header row (e.g., 'first_name').

Value

The data inside a cell. Can be a string, number, or boolean.

Tips for Clean JSON

Unique Headers: Ensure every column has a unique header name. Duplicate headers can cause data overwrite.
No Empty Header: Avoid empty cells in the first row. JSON keys cannot be empty.
CamelCase: For best coding practice, use camelCase for your headers (e.g., 'userEmail' instead of 'User Email').

Engine Specs

Input FormatCSV, TXT

Output FormatJSON

Output StyleArray of Objects

EncodingUTF-8

SpeedInstant

Security Encrypted

Private & Secure

We process files in-memory and delete them instantly. Your data never leaves our secure environment.

GDPR Compliant

Trusted by Devs

"I use this to mock API responses. Just write a CSV and convert. Super fast."

Mike R.

Full Stack Dev

"Clean output. It handles quotes and commas inside cells perfectly."

Jenny W.

Data Scientist

Common Questions

How are calculations handled?

Calculated values in CSV are just text numbers. We export them as numbers in JSON. Formulas are not preserved.

Does it support large files?

Yes, but extremely large CSVs (100MB+) might take a moment. The resulting JSON will be significantly larger in file size.

Can I customize key names?

The JSON keys are exactly what is in your CSV header row. You should rename columns in your CSV before uploading.

Is the output minified?

Yes, we return a standard JSON file. You can use our JSON Formatter tool if you need to pretty-print it.

More Developer Tools