Drop the file and read it as a proper table — searchable, sortable, with every value shown exactly as it is stored. Nothing is uploaded.
Why not just open it in Excel? Because Excel edits the file as it reads it. Leading zeros vanish from postcodes and ID codes, long numbers turn into 1.23457E+14, and anything that resembles a date gets rewritten. This page shows each cell exactly as it is stored, so you can see what the file really contains before anything touches it.
| Delimiter | Comma, semicolon and tab, detected automatically. |
|---|---|
| Quotes | Quoted fields containing commas and line breaks, with "" escaping. |
| Encoding | UTF-8, with or without a byte order mark. |
| Values | Shown verbatim. Leading zeros, long identifiers and date-like text are never reformatted. |
| Sorting | Click a header. Numeric columns sort numerically, text alphabetically; blanks sink to the bottom. |
| Search | Matches across all columns and highlights the hit. The row count updates as you type. |
| Size | Held in memory, and only the visible page is drawn, so tens of thousands of rows stay responsive. |
Do I need Excel to open a CSV? No. A CSV is a plain text file; this page renders it as a table in your browser. Nothing to install.
Why does Excel ruin my CSV? It converts values as it opens them — stripping leading zeros, turning long numbers into scientific notation and rewriting anything that looks like a date. This viewer never changes a value.
Does the file leave my computer? No. There is no server behind this page. The file is read with the browser's File API and rendered locally. Once loaded, it keeps working with the network off.
How large a file can it open? Tens of thousands of rows stay responsive because only the visible page is drawn. Million-row files belong in a database.
Sheet Insights takes the same file further — executive summary, trends with forecasting, a statistics centre, data-quality checks and one-click cleaning. Same rule as this page: everything runs in your browser, with no server behind it.
See what Sheet Insights does