Email attachment size limits in 2026 (and how to fix them)

The real limits

• Gmail — 25 MB total per email (attachments above 25 MB are auto-replaced with a Google Drive link).
• Outlook.com / Microsoft 365 — 20 MB by default; corporate Exchange admins often lower this.
• Yahoo Mail — 25 MB.
• Apple iCloud Mail — 20 MB (Mail Drop kicks in for larger files, sending a link instead).
• ProtonMail — 25 MB across all attachments.

Important catch: most providers count encoded attachment size, which is roughly 1.37× the file size on disk. A 20 MB folder of photos can become a 27 MB email and bounce.

Why this happens so easily

A 12 MP photo from a recent iPhone or Android is typically 3–6 MB. Five vacation pictures already push you to the limit. iPhones taking photos in HEIC and converting on send can actually inflate the size further.

The 60-second fix

1. Open iPhoto Resize in your browser.
2. Drag every photo you want to send into the upload area. You can drop a whole folder.
3. Set Resize by → Width → 1600 px. That's plenty for full-screen viewing on a recipient's laptop or phone.
4. Format → JPG, quality 80.
5. Hit resize. You'll get a single ZIP back — but most of the time the resized photos are small enough that you can attach them individually instead.

Typical result: 10 phone photos go from ~50 MB to ~3 MB combined. Your email sends immediately and the recipient still sees crisp images on every device.

When to use a link instead

If you genuinely need to share originals (photographer delivering RAW files, designer sending source PSDs), don't fight the attachment limit. Upload to Google Drive, Dropbox, WeTransfer, or iCloud and send a link. For everything else — family photos, work screenshots, marketing assets — resize first and attach.

Privacy note

Because iPhoto Resize runs entirely in your browser, your photos never leave your device, even temporarily. That's the right default for personal email — you don't want a third-party "online resizer" holding onto your family pictures.