JSON to CSV Converter
Flatten a JSON array into CSV.
How to use JSON to CSV Converter
Convert an array of flat objects into CSV text with a header row from the keys.
Open JSON to CSV Converter on toolpermarket — the form is ready, so type your numbers and read the result.
In the JSON field, paste a JSON array of flat objects with string or numeric values. All objects are flattened using the union of their keys as columns.
Press Convert to compute the result. The output appears immediately below the form. Edit a value and press the button once more to see the updated answer.
Read the result and use it as needed. If the number looks off, re-check your inputs and run it again — the math is deterministic, so the same entries always return the same answer.
Worked example. An array of {"name":"Jane","age":30} and {"name":"Bob","age":25} becomes a CSV with a "name,age" header and two rows.
Tips for accurate results.
The header is built from every key seen across the objects, so later objects can add columns.
Values containing commas or newlines are wrapped in quotes automatically.
Objects nested more than one level are stringified, so keep the array flat for clean output.
When to use JSON to CSV Converter. Exporting API results into a spreadsheet. Sharing structured data with someone who only opens CSV. Building a quick table from program output.
When you actually reach for this
- You need to open API JSON in Excel or Google Sheets for a non-technical teammate.
- You are flattening a list of uniform objects into a report-ready table.
Where this tool stops being accurate
- Nested objects and arrays do not fit a flat grid; they get stringified into one cell or dropped, losing structure.
- If objects in the array have different keys, some rows will have empty cells for missing fields.
Frequently asked questions
What becomes the header row?
The union of all keys found across the objects. If the first object lacks a key that a later one has, that column still appears and earlier rows get a blank cell.
Are commas and quotes escaped?
Yes. Any value containing a comma, quote or newline is wrapped in double quotes with internal quotes doubled, which is the standard CSV escaping rule.
Can it handle nested objects?
It expects a flat array. Nested values are converted to their string form, so for clean columns keep each object one level deep.
My nested fields disappeared in the CSV — can I get them back?
Flatten the JSON first (dot-notation keys like user.name) or accept that deep structures become one quoted cell. This tool handles one level of nesting as text.
Why are some rows shorter than others?
Not every object had the same keys, so the union of columns leaves gaps. That is expected for heterogeneous JSON.