Compress an Excel spreadsheet
Make a .xlsx small enough to email by recompressing oversized photos inside it. Text, formatting and everything else stay exactly the same.
Runs on your device · 0 bytes uploaded
How to compress Excel
- Add one .xlsx file (from Excel or Google Sheets).
- Choose Balanced or Strong compression.
- Click “Compress Excel” and download the smaller file.
Private by design — and you can check
Your files are never uploaded, because there is nowhere to upload them to.
- No upload step existsFiles are read and written inside this browser tab. There is no server that could receive them.
- The browser enforces itThis page’s Content Security Policy only allows connections back to this site, which serves nothing but the app itself.
- See for yourselfOpen developer tools, watch the Network tab and run a job: no request carries your document.
- Open sourceEvery line is on GitHub, built on qpdf, pdf.js and pdf-lib.
Frequently asked questions
Are my files uploaded anywhere?
No. ZapDoc does the work inside your browser tab, using open-source engines compiled to WebAssembly and JavaScript. Your file is read from your device, processed locally, and the result is saved straight back to your device. You can check this yourself: open your browser’s developer tools, go to the Network tab, and run a job — no request carries your file.
How much smaller will it get?
Files with large photos often shrink by half or more. Files that are mostly text are already compact; if ZapDoc cannot make a file smaller, it tells you and keeps the original.
Does it work with Google Sheets?
Yes. In Google Sheets, choose File → Download → Microsoft Excel (.xlsx), then add that file here. Nothing is sent to Google or to us.
Is ZapDoc free?
Yes. There is no sign-up, no watermark and no daily limit. ZapDoc is open source under the MIT license.
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- Delete PDF PagesRemove pages you don’t want to share.