How to Send Large Photos by Email: Attachment Limits and Compression

You select a dozen holiday photos, press send, and the email refuses to go: "attachment too large". Phone photos are big, often 3–6 MB each, and every email service puts a cap on how much you can attach. The fix is either to make the photos smaller or to stop attaching them at all and send a link.

This guide explains the real limits, why fewer photos fit than you expect, how to shrink photos without making them look bad, and how to choose between compressing and sharing a link.

The Limits of Popular Email Services

Sources: Microsoft Support for Outlook.com; university help desks such as Hamilton College and Tom's Guide for Gmail.

Two details matter:

• The limit applies to the whole email, not each file. Five 6 MB photos are 30 MB together and will not fit.
• The recipient's limit matters too. Even if your service allows a large email, the receiving server can reject it. Company inboxes are often stricter than Gmail.

Why Fewer Photos Fit Than You Expect

Email was designed for text. To send a photo, your email app converts the file into text characters using an encoding called Base64. That conversion turns every 3 bytes of the file into 4 characters, which makes attachments about 33% larger, and a few percent more once line breaks and headers are added (Wikipedia: Base64).

So the real budget for files is smaller than the advertised limit:

With typical phone photos of 3–6 MB, a 25 MB email realistically holds only three to five original photos. That is why a batch of "only 20 MB" fails.

Option 1: Shrink the Photos (Best for Viewing on Screens)

Most people who receive your photos will look at them on a phone or laptop. A 12- or 50-megapixel original is far bigger than any screen can show. A phone screen is around 1080–1440 pixels wide; even a 4K monitor is 3840 pixels wide. Reducing the photos to a sensible size makes them load faster and look exactly the same at normal viewing size.

What Size to Use

At around 2000 pixels and quality 80, you can usually fit 15 to 20 photos in one email instead of four.

How to Do It

1. Resize first. Use the resize tool and set the longest side to about 2000 pixels with the aspect ratio locked. Resizing gives the biggest saving: halving the width and height cuts the pixel count to a quarter.
2. Compress second. Run the resized photos through the image compressor at a quality of about 80, and compare the before and after preview.
3. For many files at once, the bulk compressor handles up to 100 images and gives you a single ZIP. It changes the quality setting but keeps each photo's pixel size, so for very large phone photos, resizing them first still makes the biggest difference.
4. Convert HEIC to JPG. iPhone photos are often HEIC files, which some recipients cannot open, especially on Windows. Convert them with HEIC to JPG before sending.

All of these tools run in your browser, so your personal photos are processed on your own device and not uploaded to a server.

For a deeper explanation of quality settings, see how to compress images without losing quality.

Shortcut on iPhone

When you attach several large photos in Apple's Mail app on iPhone, it often asks which size to send: Small, Medium, Large or Actual Size. Choosing Large gives a good balance for viewing on screens. This option depends on the app and iOS version, and Gmail's app does not offer it, so the tools above are the reliable route.

A Note on ZIP Files

Putting photos in a ZIP file does not make them meaningfully smaller. JPG and HEIC are already compressed formats, so a ZIP of them is almost the same size as the photos themselves. ZIP is useful to keep many files together as one attachment, but you still need to resize or compress the photos to save space.

Option 2: Send a Link Instead (Best for Originals and Big Batches)

If the recipient needs the full-quality originals, for printing, a photo book, professional editing or an official record, do not compress them. Upload them to cloud storage and email a link:

• Gmail and Google Drive: when you attach files over 25 MB, Gmail offers to upload them to Drive and insert a link. You can also upload a whole folder to Drive yourself and share it.
• Outlook and OneDrive: Outlook.com can share large files as OneDrive links, which do not count towards the 25 MB limit.
• Other cloud storage: Dropbox, iCloud Drive and similar services work the same way.

When you share a link, check its permissions:

• Choose "Anyone with the link can view" only if you are comfortable with the photos being forwarded.
• For private family photos, share with specific email addresses instead, so only those people can open them. Some recipients will then need to sign in with an account from the same service.
• Remove access when it is no longer needed.

A link has other advantages: the recipient chooses what to download, the email itself stays tiny, and you can add more photos to the shared folder later without sending another email.

Option 3: Split Into Several Emails

For a handful of photos slightly over the limit, sending two or three emails is fine. Number them in the subject line ("Wedding photos 1 of 3") so nothing is missed. For anything bigger, a shared folder is easier for everyone.

Before You Send: Check the Hidden Data

Photos from a phone usually contain hidden information, called EXIF metadata: the date and time, the phone model and often the GPS location where the photo was taken. When you email the original file, that information goes with it.

That is harmless when sending holiday photos to family, but think twice when emailing photos of your home, your children or anything else location-sensitive to people you do not know well, such as buyers, landlords or online contacts. The metadata remover strips location and camera details in your browser before you send.

Which Option Should You Use?

Common Mistakes

• Compressing twice. If you compress a photo hard, and then your email app or the recipient's system compresses it again, the quality drops sharply. Compress once, at a moderate setting.
• Shrinking too far. Photos of 600 pixels look fine in a phone preview but blurry when opened full screen on a laptop. Around 2000 pixels is a safe middle ground.
• Sending screenshots of photos. A screenshot is lower quality than the photo itself and may include your phone's status bar. Attach the actual photo file.
• Forgetting the recipient's limit. Company inboxes may reject large emails silently. If someone says they never received it, use a link.
• Sharing a public link to private photos. Restrict access to the people who need it.

Frequently Asked Questions

What is the attachment size limit in Gmail?

Gmail allows up to 25 MB of attachments per email, counting all files together. If you attach more, Gmail offers to upload the files to Google Drive and send a link instead.

Why does my 20 MB of photos fail to send when the limit is 25 MB?

Email converts attachments to text using Base64 encoding, which makes them roughly a third larger. About 19 MB of files can become more than 25 MB once encoded, so plan to keep the total of your files well under 18 MB.

Does zipping photos make them smaller for email?

Barely. JPG and HEIC photos are already compressed, so a ZIP file of them is almost the same size. A ZIP is useful for keeping many files together, but to make photos smaller you need to resize or recompress them.

What size should photos be for email?

For viewing on screens, about 2000 pixels on the longest side at JPG quality 80 is plenty. Such a photo is usually 300 KB to 800 KB, so 15 to 20 photos fit in one email. For printing, send the originals through a cloud link instead.