You have a .csv export and no spreadsheet application to hand, or one that mangles it on opening. Upload it to the Excel viewer and it renders as a table in the browser: CSV up to 20 MB, free, no account, deleted when you close the tab.

A CSV file rendered as a table in the browser

Why a CSV is more trouble than it looks

CSV is barely a format. It is a convention, and the conventions disagree, which is why the same file opens correctly in one program and as nonsense in another.

The separator is not always a comma. Exports from systems set to a European locale routinely use a semicolon, because the comma is the decimal mark there. A file that arrives as one long column per row has usually been split on the wrong character.
The encoding is rarely stated. A CSV carries no declaration of its own encoding, so a UTF-8 export read as Windows-1252 turns every accented character into mojibake. This is the single most common reason a CSV "looks corrupted".
Leading zeros and long numbers. A spreadsheet that opens a CSV will happily read 00123 as 123 and a 16-digit reference as a number in scientific notation. The text in the file is intact; what you are seeing is an interpretation of it.
Quoted fields containing separators. A comma inside a properly quoted field is data, not a boundary. A naive reader disagrees.

What the viewer gives you

⚡ No download, no install: the table renders in the browser, so you can check an export without opening a spreadsheet application at all.
🌐 Any device: rendering happens on our servers, so a phone or an old laptop displays a wide file as readily as a workstation.
🔒 Nothing kept: the upload runs over HTTPS and the file is deleted when the viewing session ends. There is no account and no storage — and consequently no certification we could claim, so keep genuinely sensitive data on your own systems.

One thing to be clear about: this shows you the data, it does not chart it. There is no visualisation, no filtering and no editing — it is a viewer, and it does not convert the file either.

Getting started

There is no account to create. Go to the Excel viewer, drop the file on the page, and read it.

The same viewer takes XLS, XLSX and ODS alongside CSV, up to 20 MB. If you are looking at a spreadsheet rather than a plain CSV, remember that a viewer does not recalculate: the numbers on screen are the ones the application stored at its last save.

Open the Excel viewer and check your export.