Convert JSON to CSV and CSV to JSON
Files of hundreds of MB, nested objects and Excel-ready CSV. Everything runs in your browser: nothing is uploaded.
- Free
- No sign-up
- Nothing uploaded
- Large files
- Excel-ready
Paste JSON or CSV, or drop the file: the tool detects the format, shows the columns and first rows, and converts the whole file in chunks inside your browser. Use it for API exports, database dumps, Shopify, Google Analytics or JSON Lines logs, even at hundreds of MB, and get a CSV that opens cleanly in Excel.
How to convert JSON to CSV
Paste or drop your file
JSON, JSON Lines or CSV. The format, and the CSV delimiter, are detected automatically.
Check columns and rows
See the first rows in a table and pick which columns to keep. Nested objects become dotted columns like user.city.
Download or copy
The full file is converted in chunks in your browser. Download an Excel-ready CSV or the JSON.
What makes it different
Files of hundreds of MB
Reads the file in chunks in the background: the tab doesn't freeze and you see the row count.
Your data isn't uploaded
The conversion happens in your browser. Neither the file nor its contents reach any server.
CSV that Excel opens correctly
Choice of delimiter, UTF-8 mark so accents display correctly, and formula protection.
Nested JSON without losing data
Objects are flattened into dot paths and lists are joined, kept as JSON or split into one column per position.
Both directions
JSON to CSV and CSV to JSON, with delimiter detection, number typing and rebuilt objects.
Pick your columns
Preview of the first rows and a picker to drop the columns you don't need.
What people use it for
API responses
Turn the list of results from an API into a table, even when it's inside a key like data or results.
Open data in Excel
Convert JSON to CSV and open it in Excel or Google Sheets with each field in its own column.
Database exports
Convert MongoDB, Firebase or Supabase dumps to CSV, or a CSV to JSON for importing.
Analytics and logs
Bring JSON Lines events and logs of hundreds of MB into a spreadsheet.
Stores and CRMs
Prepare product or customer CSVs from the JSON that Shopify, WooCommerce or your CRM gives you.
Data for AI
Turn a CSV into JSON or JSON Lines for a dataset or prompt without uploading the data elsewhere.
Compared with other converters
Most online converters upload your file to their server or load it all into memory and hang on a few MB.
- Here the file never leaves your browser: fine for customer, order or log data.
- Reads in chunks in the background: hundreds of MB without freezing the tab.
- Detects the format: array, JSON Lines or a list inside an object.
- Excel-ready CSV: delimiter choice, correct accents and formula protection.
- Free, no sign-up, no watermark and no row limit.
Frequently asked questions
How do I convert JSON to CSV for Excel?
Paste the JSON or drop the file, keep the UTF-8 mark on and download the CSV. Excel opens it with each field in its own column. If your Excel uses semicolons, as in many European locales, choose the semicolon delimiter.
Can I convert a JSON file of 100 MB or more?
Yes. The file is read in chunks in the background, so the tab doesn't freeze and you see progress in rows. The real limit is your device's memory; on a normal computer, files of hundreds of MB work.
Is my data uploaded to a server?
No. The conversion happens in your browser and the file isn't sent anywhere, which makes it safe for exports with customer or order data.
What happens to nested objects and arrays?
Objects become dotted columns such as address.city. Arrays can be joined into one cell, kept as JSON, or split into one column per position like tags.0 and tags.1.
Why does Excel show everything in one column or garbled accents?
Excel expects your locale's delimiter (comma or semicolon) and needs a UTF-8 mark to read accented characters. Pick the matching delimiter and keep the UTF-8 mark on.
How do I convert CSV to JSON?
Choose CSV → JSON and paste the CSV or open the file. The delimiter is detected, the first row becomes the keys, and you can type numbers and true/false, rebuild objects from dotted columns and pick a JSON array or JSON Lines.
Does it work with JSON Lines or an API response?
Yes. It accepts a JSON array, JSON Lines (NDJSON) and an object that holds the list inside a key such as data or results; in that case it uses that list and tells you which one.