What is CSV to JSON Converter?
Bidirectional CSV ↔ JSON converter. CSV to JSON: transforms tabular data into an array of key-value objects, auto-detecting headers from the first row. JSON to CSV: flattens object arrays into tabular format. Supports custom delimiters (comma, tab, semicolon), quote handling, and null value treatment. Suitable for data import/export, API format conversion, and Excel/Google Sheets migration. All processing runs locally in your browser.
▶Use Cases5 scenarios
- ◆Importing Excel data into web apps
- ◆Converting API responses to tabular format
- ◆Database export format conversion
- ◆Google Sheets ↔ JSON config exchange
- ◆Data cleaning and format normalization
▶How to Use4 steps
- 1Choose conversion direction (CSV→JSON or JSON→CSV)
- 2Paste source data or upload a file
- 3Set delimiter and options
- 4Preview and copy the result
▶Features5 features
- ✓Bidirectional conversion
- ✓Custom delimiters
- ✓Header auto-detection
- ✓Null value handling
- ✓Live preview
▶FAQ7 questions
What is CSV to JSON Converter?
An online CSV ↔ JSON converter. Bidirectional conversion with custom delimiters and live preview. Supports multiple input formats with one-click copy or download. All operations run locally in your browser — no uploads.
Does the CSV need headers in the first row?
Recommended. By default, the first row becomes JSON keys. If your first row is data, disable "First row as headers" — the tool will auto-generate field_1, field_2, etc.
Does it support tab-separated (TSV) files?
Yes. Select "Tab" as the delimiter to handle TSV files. Semicolons, pipes, and custom delimiters are also supported.
What if my CSV data contains commas?
Standard CSV wraps fields with commas in double quotes (e.g., `"Hello, World"`). The tool follows RFC 4180 and correctly handles quoted commas.
Can nested JSON objects be converted to CSV?
One level of nesting is supported. Nested objects are flattened to `parent.child` column names. For deeper nesting, flatten first.
Is my data uploaded anywhere?
No. All conversion runs locally in your browser. Nothing is sent to a server.
Can it handle large files?
Yes — files up to tens of MB work fine. For very large files (>100MB), processing may take longer. Consider splitting into batches.