JSON to CSV Converter

Convert JSON to CSV — transform API data for Excel and database import

Modern APIs return data in JSON format. Spreadsheet users, data analysts, business intelligence teams, and database administrators frequently need to import this API response data into Excel, Google Sheets, SQL databases, or BI tools like Tableau and Power BI — all of which prefer CSV as the universal import format. ToolJiffy JSON to CSV Converter transforms any JSON array of objects into a properly formatted, RFC 4180-compliant CSV file instantly in your browser, handling nested objects, missing keys, special characters, and custom delimiters.

How JSON to CSV conversion works

The conversion follows a well-defined pipeline:

1. Parse JSON: The input JSON string is parsed using JSON.parse(). ToolJiffy validates the JSON and reports any syntax errors with line/column information before attempting conversion.
2. Detect structure: Supports JSON arrays of objects ([{...}, {...}]) and single JSON objects that should be expanded to one CSV row.
3. Flatten nested objects: Nested objects like {"address": {"city": "London", "zip": "SW1A"}} are flattened to dot-notation columns: address.city, address.zip.
4. Collect all headers: All unique keys across all objects in the array are collected as CSV column headers — objects missing certain keys get empty cells for those columns.
5. Serialize to CSV: Values are serialized per RFC 4180 — values containing the delimiter, double-quotes, or newlines are quoted; internal double quotes are doubled.

Nested JSON flattening strategy

Real-world JSON API responses are rarely flat. ToolJiffy handles nested structures with configurable strategies:

• Dot-notation flattening: {"user": {"name": "Alice", "age": 30}} → columns user.name, user.age
• Array of primitives — join: {"tags": ["a", "b", "c"]} → single column tags with value "a;b;c"
• Nested arrays of objects — serialize: Deep nested object arrays are serialized as JSON strings within a single CSV column for manual parsing
• Max depth limit: Configure maximum flattening depth (default: 3 levels) to prevent excessively wide output from deeply nested data

RFC 4180 CSV compliance for maximum compatibility

ToolJiffy produces CSV output compliant with RFC 4180 (the de facto CSV standard), ensuring compatibility with Excel, Google Sheets, Python pandas pd.read_csv(), R read.csv(), and SQL LOAD DATA commands:

• Fields containing commas are enclosed in double quotes
• Fields containing double quotes have internal quotes doubled: "Alice ""The Great"" Smith"
• Fields containing newlines are enclosed in double quotes
• UTF-8 BOM (\uFEFF) optionally prepended for Excel Windows compatibility

Step-by-step guide to converting JSON to CSV

1. Paste your JSON: Enter or paste your JSON array of objects into the editor above (or upload a .json file).
2. Configure options: Choose delimiter (comma/semicolon/tab), flattening depth, and whether to include a BOM for Excel.
3. Convert and download: Click Convert to CSV and either copy the CSV output or click Download CSV to save as a .csv file.

Frequently asked questions

How does the JSON to CSV Converter work in browser memory?

ToolJiffy parses JSON, flattens nested objects using dot-notation key paths, extracts unique keys as headers, and serializes each row — running 100% in browser memory with no server uploads.

Does JSON to CSV handle nested objects and arrays?

Yes. Nested objects are flattened to dot-notation columns. Nested arrays of primitives are joined with semicolons. Deeply nested arrays are serialized as JSON strings.

Is my JSON data uploaded to any cloud server?

No. All JSON parsing and CSV serialization run 100% locally in your browser. Your data never leaves your device.

What happens if JSON objects have inconsistent keys?

All unique keys across all objects are collected as headers. Objects missing a key get an empty cell in the corresponding CSV column.

Can I customize the CSV delimiter?

Yes. Choose comma (standard CSV), semicolon (European locale), or tab (TSV) as the field delimiter.

Does the converter handle values containing commas, quotes, and newlines?

Yes. Values are automatically escaped per RFC 4180 — wrapped in double quotes, with internal quotes doubled.

Can I download the converted CSV file directly?

Yes. Click 'Download CSV' to trigger a browser file download with the correct Content-Type and optional BOM for Excel compatibility.

Is ToolJiffy JSON to CSV Converter free without limits?

Yes. ToolJiffy is 100% free with unlimited data conversion, zero account registration, and zero server uploads.

Related data conversion tools

Convert CSV to JSON with CSV to JSON Converter, format JSON with JSON Formatter, validate JSON with JSON Validator, or convert XML to JSON with XML to JSON Converter.