OnlineCSV
100% Client-Side Privacy — Your files never leave your browser

Free Online CSV Tools

View, edit, convert, clean and analyze CSV files directly in your browser. Fast, private and no signup required.

Drop your CSV file here to view instantly

Private in-browser parsing. Zero server uploads.

CSV, TSV, XLSX, TXT• Private in-browser processing

CSV Tool Directory

Select a utility below to view, convert, clean, or transform your data.

Your Files Stay Private

OnlineCSV runs entirely inside your web browser. Your CSV files are processed locally and are never uploaded to any remote server.

Lightning Fast Engine

Engineered with high-performance virtualized tables and streaming web workers. Open datasets with 100,000+ rows without freezing your UI.

No Signup Required

Enjoy instant access to all converters, clean tools, validators, and row counters without login barriers, accounts, or rate limits.

Frequently Asked Questions

What is OnlineCSV?

OnlineCSV is a free collection of browser-based CSV utilities that allow you to view, edit, convert, sort, filter, merge, split, and validate CSV files directly in your web browser.

Are my CSV files uploaded to a server?

No. OnlineCSV's core file tools process your CSV locally inside your browser using JavaScript. The file content does not need to be uploaded to our server for processing.

Can I open a CSV file without Microsoft Excel?

Yes! You can open, view, search, and edit any CSV file instantly using our free CSV Viewer or CSV Editor directly in Chrome, Firefox, Safari, or Edge.

Can OnlineCSV handle large CSV files?

Yes. OnlineCSV utilizes virtualized rendering that only renders DOM elements for rows currently visible on your screen, allowing files with tens of thousands of rows to run smoothly.