Converter Tools
Convert and transform data between formats. CSV to JSON, TSV to CSV, delimiter converters — all free and 100% private in your browser.
Date & CSV Date Tools
Data Converters
Data format conversion made simple
Working with data often means moving between formats. FormatList's converter tools help you transform data quickly — whether you're migrating between systems, preparing data for analysis, or integrating with APIs.
Why use our converter tools?
- Date Format Fixer — Detect ambiguous US vs UK dates, batch-fix CSV date columns, and export ISO 8601 before your data hits Excel or an API. See also the Ambiguous Date Checker and UK Date to US Date converters.
- CSV to JSON — Convert spreadsheet exports to structured JSON arrays for API integration. Supports customizable delimiters, header detection, and file upload.
- TSV to CSV — Transform tab-separated database exports to universal CSV format. Handles quoted fields, embedded delimiters, and special characters.
- Comma Separator — Turn newline-separated lists into comma-separated, SQL IN clauses, JSON arrays, Python lists, and Markdown tables.
Common workflows
- Fix date columns after Excel corrupted a CSV import — see our Excel CSV date import guide.
- Export data from a database as TSV, convert to CSV, then import into a spreadsheet.
- Transform CSV exports into JSON for REST API payloads.
- Prepare lists of IDs for SQL queries with the comma separator tool.
Converter Tools FAQ
Are these converter tools free?
Yes. All converter tools on FormatList are 100% free with no signup, no ads, and no usage limits.
Is my data sent to a server?
No. All conversion happens locally in your browser. Your data never leaves your computer.
Can I convert large files?
Yes. The tools handle files up to your browser's memory limit. For very large files, consider splitting them first.
What formats are supported?
Currently we support CSV, TSV, JSON, and list/delimiter conversions. Markdown-specific tools live under the Markdown Tools category.