About The JSON to CSV Converter

The JSON and CSV Converter moves tabular data between JSON and CSV formats. It is built for API samples, spreadsheet imports, export cleanup, quick test fixtures, and small data transformations where opening a larger data tool would slow you down.

JSON to CSV accepts one object or an array of objects. Nested object fields are flattened with dot notation, so a value like user.name can become a CSV column. CSV to JSON expects a header row and returns an array of objects.

How to Convert JSON and CSV Online

1. Paste a JSON object or array of objects into JSON input, then click Convert to CSV.
2. Paste CSV with a header row into CSV input, then click Convert to JSON.
3. Review the status message if the input is malformed or not the expected shape.
4. Use the matching Copy Output button beside the result you want to keep.

Choosing Input Shape Correctly

JSON to CSV:
Use an object for one row or an array of objects for multiple rows. Arrays of strings, numbers, or mixed primitive values are rejected because they do not provide column names.

CSV to JSON:
The first row is treated as column headers. Blank header names are replaced with generated names like column_1, and missing cells become empty strings.

Common Use Cases

• Turn API response rows into CSV for spreadsheet review.
• Create JSON test payloads from a small CSV sample.
• Flatten nested response fields before sharing data with a non-JSON workflow.
• Check whether a CSV export has quote or delimiter issues before importing it elsewhere.

Quick FAQ

Does this handle deeply nested JSON?
It works best with arrays of similar objects. Deeply nested data may need flattening or manual field selection before it becomes useful CSV.

Why does my JSON array fail?
The input may not be valid JSON, may not be an array of records, or may mix incompatible structures.

Does the conversion run locally?
Yes. The conversion is designed to run in the browser.

Why are some CSV cells blank?
A blank cell usually means that record did not contain the selected key, or the value was nested where a flat CSV column cannot represent it directly.