Outlook attachment size limit
Outlook attachment size limit guide. Free, private, and processed on your device.
1 Shrink your PDF locally to under 20 MB.2 Attach the compressed copy in Outlook.3 Send directly without triggering OneDrive prompts.
About this tool
Microsoft Outlook limits email attachments to 20 MB or 25 MB depending on server config. When a file is too large, Outlook blocks delivery or prompts for OneDrive. Compressing your PDF locally before attaching keeps the document beneath the threshold without sending files to external sites.
Outlook attachment size limit is processed entirely on your device. Your original file remains untouched, and nothing is ever uploaded to a server or saved in the cloud.
- No upload: local processing keeps your email attachments private.
- Speed: processing happens instantly on your device with no upload or download delays.
- Quality: you can check your file before saving, and the original remains unchanged.
FAQ
Does “Outlook attachment size limit” upload my file?
Outlook attachment size limit processes your file locally in this browser tab. There is no upload step and no account required.
What will “Outlook attachment size limit” actually change?
Outlook caps default attachments at 20–25 MB.
When is “Outlook attachment size limit” the wrong job?
Local compression shrinks images inside the PDF without uploading.
How do I check the result of “Outlook attachment size limit”?
Review pages before sending important contracts.
Can I run “Outlook attachment size limit” with Wi-Fi off?
You can turn off Wi-Fi after loading this page and Outlook attachment size limit still works completely offline.
Compress PDFCompress PDF for emailCompress PDF to 2 MB
Last updated 2026-09-27.