How to use JSON to CSV
- 1
Open the JSON to CSV converter
Go to tools.slaytic.com and open the JSON to CSV tool. No sign-up or account required.
- 2
Paste or drop your JSON
Supply an array of objects. If your data is wrapped in a response envelope, extract the inner array first.
- 3
Download the CSV
Save the flat table, ready to open in Excel or import elsewhere.
How this works in your browser
The JSON is parsed and every object in the array is inspected to build the union of all keys present, which becomes the column set. Taking the union rather than reading the first object matters: real API data is frequently uneven, and assuming the first record defines the shape silently discards fields that appear later. Nested objects are flattened into dot-notated column names, which works because an object has a fixed set of named children that map naturally onto columns. Arrays do not, since their length varies per record while a table’s width cannot, and that mismatch is a property of the two formats rather than something a converter can solve elegantly.
JSON to CSV vs. traditional online converters
| Feature | JSON to CSV (in-browser) | Traditional online converters |
|---|---|---|
| File upload required | No - never leaves your device | Yes - file is sent to a server |
| Processing queue | None - starts instantly | Often, especially at peak times |
| Watermark on output | Never | Common on free plans |
| Usage limits | None - free, unlimited use | Often capped per day or file size |
| Works offline once loaded | Yes, for most tools | No - requires a live connection |
| Account required | No | Often, for anything beyond a trial |
Who uses JSON to CSV
Analysing API responses
Turn returned JSON into a table you can sort, filter and chart in a spreadsheet.
Sharing data with non-developers
Give colleagues a file they can open rather than a block of JSON.
Reporting from exported data
Convert a system export into a spreadsheet for a report or reconciliation.
Bulk import preparation
Produce the CSV format most import tools and upload forms require.
Frequently asked questions
What JSON shape works best?
An array of flat objects with consistent keys converts most cleanly, for example [{"name":"...","email":"..."}, ...].
What happens with nested objects inside the JSON?
Nested objects are flattened into dot-notated column names where possible, since CSV has no native concept of nesting.
What if some objects are missing certain keys?
Missing keys produce an empty cell in that row’s corresponding column.
How are arrays inside my objects handled?
This is the honest weak point of the conversion, and it is inherent to CSV rather than to the tool. A row is a fixed set of cells, so a property holding a list of tags or line items has nowhere natural to go. Expect it to end up serialised into a single cell. If the arrays are the interesting part of your data, CSV is the wrong destination.
My API response will not convert. Why?
Usually because it is an object wrapping the array rather than the array itself, something like a results or data property containing the records. Extracting that inner array and converting it alone is what produces a sensible table.
Why did I get columns I did not expect?
Because every unique key across all objects becomes a column, so one record with an extra field adds a column that is empty for everything else. That behaviour is deliberate, since silently dropping fields present in only some records would lose data.
Is my data uploaded anywhere?
No. The JSON is parsed and the CSV written inside your browser tab.