About
CSV Checker is a tool that validates and compares CSV files in your browser.
About this service
This service is a personal project developed to streamline data processing. It was created to make CSV quality checking and comparison easier.
What is CSV Checker?
CSV Checker provides the following features.
Single-file check
Validates one CSV: format, encoding, header, delimiter, empty rows, column count mismatch, and more.
Compare two files
Compares two CSVs and shows added, deleted, and changed rows with colour highlighting.
Encoding fix (garbled text)
This tool converts garbled CSV or text files to UTF-8 (with BOM) entirely in your browser. Files are never uploaded to a server; all processing happens on your device.
Features
- Drag & drop: Drop a file on the area to start conversion.
- Auto encoding detection: Detects Shift-JIS, EUC-KR, CP949, and others, then decodes the file correctly.
- Manual encoding: If auto-detect is wrong, choose the source encoding from the dropdown.
- Preview: View the first 10 lines of the converted text to confirm it looks correct.
- UTF-8 BOM download: Saves in a format that opens correctly in Excel. The file is named
fixed_originalname.
Supports CSV as well as TXT, LOG, and other text-based files. Safe for sensitive or work data since nothing is sent to a server.
Who is it for?
- Anyone who wants to validate data before uploading to a system
- Anyone who needs to quickly see differences between two lists (e.g. month-over-month)
Features
- Files are processed only in your browser and are not sent to any server. Your data stays private.
- You can try it without logging in (with limits on usage and row count). Log in or subscribe for higher limits.
Requirements
We recommend using the latest Google Chrome or Microsoft Edge for the best experience.