The real limits of email attachments
Most email providers advertise a 20-25MB attachment limit per message. That sounds generous, but the practical limit is much lower. Corporate mail servers often cap attachments at 5MB or 10MB. Some cap at 2MB. And even when a provider accepts a large attachment, the recipient's server may reject it, silently drop it, or route it to spam.
On top of that, mobile users read email on connections that are often slow. A 5MB photo that takes a second to download on Wi-Fi can take thirty seconds on a weak mobile signal. Compressing your photos before attaching them solves both problems.
What size should email photos be?
For reliable delivery across all email providers:
- 200KB per photo — perfect for a few photos in one message
- 500KB per photo — good for a single high-quality photo
- 1MB per photo — the safe upper limit for reliable delivery
If you are sending multiple photos, compress each to 200KB. A typical email with ten compressed photos stays under 5MB and delivers reliably to any provider.
Why you do not need full resolution for email
Email photos are viewed on screens — phones, laptops, tablets. They are never printed from email at high resolution. That means you do not need the full 4000×3000 resolution of a modern phone camera.
Reducing to 1600×1200 or 1920×1440 and compressing to 200-500KB produces a photo that looks identical on the recipient's screen and sends instantly.
Step-by-step
Compressing photos for email is straightforward:
- Compress each photo to 200-500KB using FITLY.
- Optionally set a max dimension of 1920px to ensure the image does not exceed typical screen resolution.
- Download the compressed files.
- Attach them to your email as normal.
That is it. The whole process takes seconds per photo, and the result is an email that sends reliably to any address.
Privacy considerations
If you are emailing sensitive images — ID documents, financial records, personal photos — avoid any tool that uploads your image to a server for processing. FITLY runs entirely in your browser. Nothing is ever uploaded.