• The 25 MB Attachment Problem: Shrinking Files Without Ruining Them
  • PDFs: the usual suspect
  • Images: resize beats re-zip
  • Video: bitrate is the lever
  • What not to do
  • The short version

§The 25 MB Attachment Problem: Shrinking Files Without Ruining Them

Almost every email provider caps attachments around 25 MB. Hit the limit and your carefully prepared proposal, portfolio, or screencast bounces back. The fix is rarely “send less stuff” - it is shrinking the right files the right way.

§PDFs: the usual suspect

Scanned PDFs are the worst offenders: each page is a full-resolution image wrapped in a PDF container. A 10-page scan easily passes 40 MB. Re-compressing the embedded images - downsampling to 150 DPI and re-encoding - typically cuts 70-80% with no visible difference on screen or in print. FileCompress has a dedicated PDF compressor that does this in the browser, no signup.

§Images: resize beats re-zip

A photo straight from a phone is 3-12 MB. Attached five of them to an email and you are already over the limit. Two moves fix it: resize to the display size you actually need (1200-1600px wide is plenty for screen), and export at 80-85% quality. That combination alone usually lands each photo under 300 KB. The image compressor handles PNG screenshots the same way - and PNGs from Retina displays are famously bloated.

§Video: bitrate is the lever

A 2-minute 4K phone recording can be 800 MB. For sharing, nobody needs 4K in an email attachment. Re-encoding to 1080p with a sane bitrate (8-12 Mbps for H.264) brings it under 100 MB, and for quick previews even 720p is fine. If your tool only offers a “quality” slider, dropping one notch is roughly a 40% saving. The video compressor runs this entirely client-side.

§What not to do

Do not ZIP a folder of JPGs and expect miracles - already-compressed formats shrink barely 1-3% inside an archive. And do not forward the bounce to IT asking for a bigger limit; the limit exists because someone has to store and scan every attachment.

§The short version

Resize images, re-compress scanned PDFs, re-encode video at a lower bitrate. Three habits, and the 25 MB ceiling stops being a problem. https://filecompress.org