Convert JSON to CSV
Turn a .json array into a flat, spreadsheet-ready CSV — right in your browser. The tool collects every key across all your objects as columns (even when they don't all match), escapes fields correctly, and lets you download the result. Nothing is uploaded.
Convert a JSON File to CSV
Drop a .json file below — an array of objects (the most common case, e.g. an API export), an array of arrays, or a single object. It's parsed and flattened to a real CSV right in your browser, previewed, and ready to download.
🔒 Nothing is uploaded — your file never leaves this deviceCSV preview
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How the JSON-to-CSV conversion works
JSON can express structure CSV can't (nested objects, arrays, differing shapes across records). Turning it into a flat table means making real decisions about how to flatten it, which this tool does transparently:
- Column detection — for an array of objects, the tool scans every object and builds the column list from the union of all keys it finds, in first-seen order, rather than assuming every object matches the first one's shape.
- Missing keys — if an object doesn't have a given key, its cell for that column is left empty, keeping every row properly aligned.
- Nested values — an object or array found as a value is serialized as compact JSON text in that cell, since CSV has no way to represent nesting natively.
- Escaping — any value containing a comma, quote or line break is quoted and escaped per RFC 4180, so the output opens correctly in Excel, Google Sheets or any CSV parser.
Why convert JSON to CSV
JSON is what most APIs return, but spreadsheets, BI tools and most non-technical collaborators want a flat table. Converting an API response or export into CSV is the fastest way to open it in Excel or Google Sheets, filter and sort it, or hand it to someone who doesn't work with JSON directly.
Edge cases this tool handles
Objects with different keys
Common with real-world API data where optional fields are sometimes omitted — the tool builds one consistent column set from every object seen, rather than only using the first object's keys.
Nested objects and arrays
Serialized as compact JSON text inside the cell, so no data is silently lost.
A single object instead of an array
Converted to a one-row CSV using that object's own keys as columns.
Values containing commas, quotes or line breaks
Correctly quoted and escaped per RFC 4180 so the file opens cleanly.
Frequently asked questions
Does converting JSON to CSV upload my file anywhere?
No. This tool parses and converts the file entirely inside your browser using JavaScript — the file's contents never leave your device or touch a server.
What if my JSON objects don't all have the same keys?
The tool collects the union of every key it sees across all objects, in the order they first appear, and uses that as the column set. Any object missing a given key simply gets an empty cell for that column, so the resulting table is always fully aligned — nothing is dropped or misaligned.
What happens to nested objects or arrays inside my JSON?
CSV can't represent nesting, so a nested object or array value is serialized as compact JSON text inside that single cell, rather than being silently dropped or exploded into unpredictable extra columns.
Does it work with a single JSON object instead of an array?
Yes — a single top-level object is converted into a one-row CSV, using its own keys as columns.
Last updated September 23, 2026.