CSV ↔ JSON Converter
Convert CSV to JSON or JSON to CSV — free, instant, no signup required
🚀 Features
Auto Type Detection
Numbers, booleans and nulls are cast to the correct JSON types automatically — no manual work.
File Upload & Download
Upload .csv or .json files and download your converted output with one click.
Multiple Delimiters
Comma, semicolon (EU format), tab (TSV), and pipe delimiters all supported.
Nested JSON Flattening
JSON → CSV automatically flattens nested objects one level deep using dot notation.
100% Private
Data is processed server-side and never stored, logged, or shared with anyone.
Completely Free
No account, no signup, no limits. Use it as many times as you like, forever.
📖 How to Use
Convert CSV to JSON
- Click the CSV → JSON tab at the top.
- Paste your CSV text into the textarea, or upload a .csv file.
- Select your delimiter — Comma for standard CSV, Semicolon for European exports, Tab for TSV.
- Click Convert to JSON. Your output appears instantly below.
- Click Copy or Download .json to save the result.
Convert JSON to CSV
- Click the JSON → CSV tab at the top.
- Paste your JSON array or upload a .json file.
- Select your output delimiter and click Convert to CSV.
- Copy or download the resulting CSV file.
Tips for Best Results
- Your CSV must have a header row — the first row is always used as column names.
- Values containing commas must be wrapped in double quotes in the CSV.
- JSON must be an array
[{...}]or a keyed object{"key": {...}}. - Nested JSON is flattened one level:
address.citybecomes a column header.
🆚 CSV vs JSON — What's the Difference?
CSV (Comma-Separated Values) is a flat, tabular format where every row has the same columns separated by a delimiter. It's the standard for spreadsheets, Excel, and database exports, but cannot represent nested data or typed values natively.
JSON (JavaScript Object Notation) supports nesting, arrays, and proper data types — strings, numbers, booleans, null. It's the standard for web APIs, NoSQL databases (MongoDB, Firebase), and configuration files.
When you need to feed spreadsheet data into a web app or API, convert CSV → JSON. When you need to export API data into Excel or a database table, convert JSON → CSV.
👥 Who Uses This Tool?
Web Developers — Feed JSON data into APIs, React/Vue components, or Node.js apps that expect JSON format instead of flat CSV.
Data Analysts — Export spreadsheet data to JSON for use in Python, Pandas, or machine learning pipelines, or do the reverse.
E-commerce Teams — Convert product catalog CSVs into JSON for Shopify, WooCommerce, or custom storefronts.
DevOps Engineers — Convert configuration CSVs into JSON for Terraform, Ansible, or CI/CD pipelines.
Mobile Developers — Turn spreadsheet content into JSON for iOS, Android, or React Native apps.
❓ Frequently Asked Questions
Yes — 100% free, no account required, no usage limits. Use it as many times as you need without paying anything.
Your data is processed on our server and immediately discarded after conversion. We never store, log, or share your data with anyone.
Yes. Select Semicolon ; from the Delimiter dropdown before converting. This is common with Excel exports in European locales where commas are used as decimal separators.
Yes. Nested objects are automatically flattened one level deep using dot notation. For example {"address": {"city": "NYC"}} becomes a column called address.city.
Yes. Integers, floats, booleans (true/false/yes/no), and empty cells (null) are all cast to the correct JSON types automatically, so you get "age": 30 instead of "age": "30".
Files up to 50 MB are supported. For larger datasets we recommend Python's built-in csv and json modules or a dedicated ETL tool.