Corrupt Excel File

What this does

Excel's built-in Open and Repair is the first and usually the only tool worth reaching for. It offers two passes: Repair rebuilds the workbook structure and keeps formulas where it can, and Extract Data pulls values (optionally converting formulas to their last calculated results) out of a file too damaged to rebuild. When both fail there are two more routes that cost nothing: opening the workbook in a different application (Google Sheets, LibreOffice and Numbers each have their own parser and sometimes read a file Excel rejects), and — for .xlsx files, which are ZIP archives — renaming a copy to .zip and extracting it to recover the embedded worksheet XML and any images. "The file format is not valid" is usually not corruption at all but a mismatched extension: a .xls file renamed .xlsx, or an HTML export saved with a spreadsheet extension. The same idea underpins a lot of everyday Excel work, so the few minutes spent getting it right here pay back across every sheet you build afterwards. Treat it as a pattern, not a one-off, and it stops being something you look up and starts being something you reach for. For “corrupt excel file”, the reliable version is a short checking loop, not just the first command that appears to work. Run it on a deliberately small range first, watch how the affected cells change, and only then apply the same setup to the full sheet. When this is a ribbon command, the selection matters more than the button: confirm the range, apply the command, then spot-check the output before saving. That is what makes a data step that keeps your analysis trustworthy useful in real work: repeatable, auditable, and not dependent on memory or luck.

A worked example

A 40 MB workbook that closed during a save now refuses to open. File ▸ Open ▸ Browse ▸ select it ▸ arrow beside Open ▸ Open and Repair ▸ Repair. Excel reports it removed a damaged chart and opens the rest with formulas intact. Save immediately under a NEW name, so the original stays available if the repair turned out to be partial. A damaged workbook is recoverable far more often than it looks, and the free routes work often enough that paying for a recovery tool should be the last step rather than the first. One habit worth forming early: name the cells that hold your inputs, so the formula reads in plain language instead of a string of cell addresses. A reviewer — or you in three months — can then follow the logic without decoding what B7 and D2 were supposed to mean, which is most of what makes a sheet maintainable.

In Google Sheets

Everything above works in Google Sheets too. Excel and Sheets share the formula syntax used here; only the surrounding menus are arranged differently. That portability is deliberate — learn it once and it follows you between the two tools and across Windows and Mac. Nothing on this page is behind a login: the tool runs entirely in your browser, the formula is shown in full with one-click copy, and the steps work the same on Windows and Mac. That is the whole promise here — the exact answer, a way to prove it on your own numbers, and just enough context to make it stick. Treat “corrupt excel file” as a small building block rather than a chore. Once the inputs sit in their own cells and the formula reads from them, the same setup answers a dozen related questions with a tweak, and Excel keeps every dependent figure current as the data changes. The tool above is there so you can rehearse and verify before committing anything to a real workbook; the steps and worked example are there so the logic sticks. Get it right once and it stops costing you time — it starts saving it, every time the question comes back around.

Common mistakes

• Repairing in place, so a partial repair destroys the only copy you had.
• Paying for a recovery tool before trying Open and Repair, another application, and the ZIP route — all free.
• Assuming "file format is not valid" means corruption when the extension simply does not match the real format.
• Ignoring the cause: a workbook that corrupts repeatedly usually points at a flaky network share, an add-in, or saving over SMB with a dropping connection.
• Overlooking AutoRecover, which often holds a version only minutes older than the damaged file.

Frequently asked questions