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CSV ↔ JSON Converter

Convert CSV to JSON and JSON to CSV securely without uploading your data. All processing happens locally in your browser for complete privacy.

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Convert between CSV and JSON formats instantly with SolveBar's CSV ↔ JSON Converter. Upload a file or paste data, see a live table preview, and download the converted output. Handles headers, quoted fields, nested values, and special characters correctly.

When to use CSV vs JSON

CSV is ideal for tabular data, spreadsheets, database exports, and data that humans need to read in Excel or Google Sheets. JSON is better for APIs, configuration files, nested data structures, and JavaScript applications.

Handling CSV edge cases

CSV seems simple but has many edge cases: fields containing commas must be quoted, fields containing quotes must have the quote doubled or escaped, and newlines within fields require quoting the entire field. This tool uses PapaParse which handles all standard CSV variations correctly.

JSON array format for CSV conversion

When converting JSON to CSV, the input must be a JSON array of objects where all objects share the same keys (which become column headers). Nested objects are flattened. The tool previews the output table so you can verify the structure before downloading.

Frequently Asked Questions

Is there a file size limit for uploaded CSV files?

No hard limit — large files process in the browser's memory. Files above 50MB may cause slowdowns depending on your device.

What encoding does the converter support?

UTF-8 is fully supported including international characters, emoji, and special symbols.

Can I convert JSON with nested objects to CSV?

Nested objects are flattened (e.g. address.city becomes a column). Deeply nested structures lose some information in the flattening — CSV is fundamentally flat.