FREE TOOLS
Free CSV tools
Three small tools for the mechanical parts of working with a CSV: looking at one, cutting one up, and turning one into a spreadsheet. Each runs entirely in your browser, so nothing uploads and there is no file size to worry about. No account needed.
CSV viewer
Open a large CSV and read it as a normal table. Rows are streamed and paginated, so a multi-GB file shows its first page straight away instead of freezing a spreadsheet.
CSV splitter
Cut one oversized CSV into smaller files, each keeping the original header row. Useful when a system downstream — Excel included — refuses anything past a row count.
CSV to Excel converter
Turn a CSV into a real .xlsx workbook. Anything past Excel’s 1,048,576-row sheet limit is spread across extra sheets automatically, so no rows go missing.
Which one do you need?
If the file will not open and you only want to see what is inside it — the column names, how the values are formatted, whether an export actually worked — use the CSV viewer. Nothing is changed; it just shows you the rows.
If something downstream refuses the file for being too big — an import limit, a colleague's spreadsheet, an upload cap — use the CSV splitter to break it into parts that each carry the header row, so every piece is still a valid CSV on its own.
If the file needs to end up as a spreadsheet — for someone who works in Excel, or for a template that expects .xlsx — use the CSV to Excel converter. Files past Excel's 1,048,576-row sheet limit are spread across extra sheets rather than silently truncated.
Why these run in your browser
Most online CSV tools ask you to upload the file first, which means waiting on the upload, trusting someone else with your rows, and hitting whatever size cap they have set. These read the file directly from your disk instead. Nothing travels anywhere, a large file starts working immediately, and data you are not allowed to send to a third party stays exactly where it is.
Questions
Are these CSV tools really free?
Yes. All three are free with no account, no sign-up, no watermark, and nothing to install. They run in your browser.
Do my files get uploaded?
No. Every tool here reads your file directly on your own computer. Nothing is sent to our servers, which is also why they stay fast on multi-gigabyte files.
How large a file can these handle?
Far larger than a spreadsheet will take. Files are streamed in chunks rather than loaded whole, so memory use stays flat; multi-gigabyte CSVs are normal for these tools.
What if I want to actually analyze the data, not just handle the file?
That is what Sifar Data itself does. These tools do one mechanical job each; the app lets you ask questions about a CSV in plain English and get answers, charts, and the SQL behind them — with the file still staying on your machine.
Need answers, not just the file handled?
Sifar Data opens CSV files with millions of rows and answers questions about them in plain English — still without uploading anything.