Data Formatters & Converters
Processed locally
JSON ↔ CSV Converter
Paste JSON or CSV — the direction is auto-detected. JSON → CSV flattens nested objects and expands nested arrays with an Excel-safe formula guard; CSV → JSON types values. Runs in your browser.
Auto-detects and converts as you type. Ctrl+Enter to re-run.
How to use the JSON ↔ CSV Converter
Convert a JSON array of objects — from an API, Postman, logs, or a database export — into clean CSV ready for Excel, Google Sheets, BI tools, or a SQL bulk load. Flip the direction to turn CSV back into JSON for tests, fixtures, and integration scripts. The converter flattens nested objects, expands nested arrays, and quotes values safely; everything runs in your browser.
What it does
- JSON → CSV: takes an array of objects and produces a CSV with a header row and consistent columns.
- CSV → JSON: produces an array of objects with typed values where possible (numbers, booleans, nulls).
- Flatten nested objects using dot-paths (e.g.,
user.name,address.city). - Custom delimiter (comma, semicolon, tab) and quote handling for Excel compatibility.
- Preserves UTF-8 characters and emoji; an Excel formula-injection guard keeps spreadsheets safe.
- Preview, copy, download, or send to CSV Viewer, SQL IN Builder, or JSON Formatter.
When to use it
- Convert a JSON API response into a spreadsheet for stakeholders.
- Export logs (newline-delimited JSON) to CSV for reporting.
- Create test fixtures in JSON from a CSV exported by analysts.
- Reformat a Postman / DevTools response for an audit trail.
- Prepare bulk-insert data for a database from a JSON dump.
- Hand off tabular results to a non-technical reviewer.
How to use it
- Paste your JSON or CSV into the input editor (or load from clipboard / file).
- The converter detects the direction automatically — JSON arrays become CSV; CSV with a header row becomes a JSON array of objects.
- Enable Flatten to expand nested objects into dot-path columns (
user.name,address.country). - Pick the delimiter and toggle the header row, value typing, and the formula guard as needed.
- Inspect the preview, then copy or download the result. Open the CSV in Excel or Sheets, or pipe the JSON to your tests.
Tips & pitfalls
- For JSON → CSV, all objects should share consistent keys — missing keys produce empty cells, not errors.
- Excel on Windows reads UTF-8 best via Data → From Text/CSV with UTF-8 selected — use that if names show as mojibake.
- Nested arrays cannot become a single CSV cell cleanly — flatten, keep as a JSON string, or expand into multiple rows.
- Quotes inside fields must be doubled in CSV (RFC 4180); the converter handles this automatically.
- Use the JSON-to-CSV direction with the JSON Formatter first if the source JSON has parse errors.
FAQ
- How do I convert JSON to CSV online? Paste a JSON array of objects, choose a delimiter, and download or copy the CSV.
- How do I convert CSV to JSON? Paste a CSV with a header row — the converter produces a JSON array of objects with typed values.
- Does it support nested JSON? Yes — enable Flatten to convert nested keys into dot-paths like
user.address.city. - Why does Excel show garbled characters? The exported CSV is UTF-8. Open it in Excel via Data → From Text/CSV and pick UTF-8, or make sure your editor keeps the file as UTF-8.
- Is the file uploaded? No. Conversion is local in your browser. Nothing is sent to a server or logged.
- How are columns chosen? All keys become columns. Nested keys are flattened to dot-path columns (or your chosen separator style); review them in the Preview tab before exporting.
Runs locally in your browser. No uploads. No analytics on pasted data.