JSON to CSV Converter

What Is a JSON to CSV Converter?

Converting JSON to CSV is one of the most common data transformation tasks in web development, data analysis, and business intelligence. APIs return data as JSON, but spreadsheet applications (Excel, Google Sheets) and database import tools expect CSV. This converter handles the transformation client-side — your data never leaves your browser. It automatically extracts headers from JSON keys and handles quoting per RFC 4180.

Example

JSON Input:

[{"name":"Alice","age":30,"city":"NYC"},{"name":"Bob","age":25,"city":"LA"}]

CSV Output:

name,age,city
Alice,30,NYC
Bob,25,LA

How to Use This Converter

Paste your JSON data into the input panel.
View the converted CSV output — it updates instantly.
Click Copy to copy the result to your clipboard.
Verify the output matches your expectations before using in production.

Developer Tips

Nested JSON objects flatten to dot-notation columns (e.g., address.city) in most converters. If your JSON has 3+ nesting levels, flatten it to 2 levels first or you will end up with 50+ columns that are mostly empty.
CSV does not support data types - everything becomes a string. Numbers like 007 lose their leading zeros, and dates may reformat unpredictably. If type preservation matters, consider JSON to Parquet instead of CSV.
Excel has a 1,048,576 row limit. If your JSON array exceeds this, split it before converting to avoid silently losing rows downstream.

Related Converters

All conversions run entirely in your browser — no data is sent to any server. For the specification, see RFC 4180 — CSV Format Specification.

Frequently Asked Questions

How does JSON to CSV conversion work?

The converter reads a JSON array of objects, extracts all unique keys as column headers, then writes each object as a row with values in the corresponding columns. Nested objects are flattened or stringified depending on the implementation.

What happens to nested JSON objects during CSV conversion?

Nested objects and arrays are typically stringified (converted to their JSON string representation) since CSV is a flat, two-dimensional format. For deeply nested data, consider flattening the JSON first or using a format like YAML that supports hierarchy.

Can I convert CSV back to JSON?

Yes — the reverse conversion treats the first row as property names and each subsequent row as an object. Use our CSV to JSON Converter for the reverse direction.

What is RFC 4180?

RFC 4180 is the formal specification for CSV (Comma-Separated Values) format. It defines rules for quoting fields that contain commas, newlines, or double quotes, ensuring CSV files are interoperable across different applications.

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