JSON to CSV Converter — Flatten Nested JSON
Convert JSON arrays, nested objects and NDJSON to CSV in your browser. Flattens nested keys into dot-path columns with delimiter and header options.
🔒 Runs entirely in your browser — nothing is uploadedTurn JSON into a spreadsheet-ready CSV
APIs, log exporters and NoSQL databases speak JSON, while spreadsheets, BI tools and import wizards usually expect CSV. The JSON to CSV Converter bridges that gap. Paste an array of objects, a single object or newline-delimited JSON, and the tool builds a table with one row per record and one column per field. The preview shows exactly how your data will look before you download it, and the CSV can be copied to the clipboard or saved as a file.
Real-world JSON is rarely flat. A customer record might contain an address object and a
list of tags. Instead of dumping those structures into a single unreadable cell, the
converter flattens them using dot paths: address.city, address.zip,
tags.0, tags.1 and so on. If you prefer to keep arrays together, switch the
array option to Keep as JSON text and each array is written as compact JSON in one column.
Handles irregular records
Objects in the same array often have different fields, especially when optional properties are omitted. The converter scans every record, collects the union of all keys in the order they first appear and fills missing values with empty cells, so no data is silently dropped. Null values become empty cells, booleans and numbers are written as plain text, and values that contain the delimiter, quotes or line breaks are quoted according to the CSV standard (RFC 4180).
Delimiters, headers and privacy
Choose a comma for most tools, a semicolon for spreadsheet programs in locales that use a decimal comma, a tab for TSV files, or a pipe when your data contains many commas. Turn off the header row when you are appending records to an existing file. All processing happens locally in your browser: the JSON you paste or drop is never uploaded, which makes the tool safe for API responses containing personal data, internal configuration or access logs. For very large files, the preview shows the first 100 rows while the download always contains every record.
How to use
- Add JSONPaste a JSON array, a single object or NDJSON, or drop a .json file.
- Choose optionsPick the delimiter, decide how arrays are handled and toggle the header row.
- Check the previewReview the flattened columns and first rows in the preview table.
- Download or copySave the CSV file or copy it to the clipboard.