Compress JPG for Email Attachments
Getting "file too large" errors when sending photos? ImagePilot helps you reduce your JPG sizes to just a few hundred KB so you can send them without any trouble.
Last updated: August 2026
Drop your images here or click to select
Supports JPG, PNG, WebP and AVIF
There is a detail about email attachments that explains a lot of confusing rejections: attachments are not sent as raw files. Email transports them in a text encoding, which inflates them by roughly a third on the way. A 20MB attachment limit therefore does not accommodate 20MB of photos — closer to 15MB of actual files, before the message body and any other attachments are counted. That gap is why a set of images that looks like it should fit sometimes does not.
The other multiplier is quantity. One phone photo might be four or five megabytes; ten of them clear most consumer attachment limits on their own. Compression is unusually effective here because the images are almost always going to be viewed on a screen rather than printed, so the resolution people attach is far beyond what the recipient will ever use.
That makes the sensible target a few hundred kilobytes per image rather than a few megabytes. At that size a photograph still looks completely normal when opened on a laptop or phone, ten of them fit comfortably inside any limit, and the recipient downloads them in seconds rather than minutes — which matters more than most senders realise for anyone reading on mobile data.
How to compress JPG files for email
- 1
Count what you are sending
Divide the attachment limit by the number of photos, then subtract a third for encoding overhead. That gives you a realistic per-image budget rather than a hopeful one.
- 2
Add your JPGs
Drop the whole set. Each is processed in your browser, so nothing is uploaded before you have even sent the email.
- 3
Target a few hundred kilobytes each
Set a size target rather than guessing a quality percentage. For on-screen viewing, a few hundred kilobytes per photo is generous.
- 4
Download and attach
Use "Download all" for the batch. The compressed files are what you attach — keep the originals if you may need them at full size later.
Pro tip: For a large set, send a link rather than attachments. Email was never designed to move dozens of photographs, and the encoding overhead plus per-message limits make it a poor transport for anything substantial. Uploading to any file-sharing service and sending the link avoids the limit entirely, arrives faster, and lets the recipient download only what they want. Compression is the right answer for a handful of images; a link is the right answer for a holiday album.
Troubleshooting: If a message is still rejected despite your files being under the limit, remember the encoding overhead and the message body both count — leave a real margin rather than aiming at the exact figure. If recipients say the photos look poor, the target was too aggressive; a few hundred kilobytes each is normally invisible, and going far below that is not necessary. If some images barely shrink, they were probably already compressed.
For specific targets, Compress JPG to 500KB and Compress JPG to 200KB are sensible per-photo budgets for email. For a whole batch at once, Bulk Image Compressor. If the images would be better as one document, Combine Images into One PDF turns a set of attachments into a single file. For images inside the message rather than attached to it, Resize Image for Email.
Frequently asked questions
How do I compress photos to email them?
Add them to the tool above, set a target of a few hundred kilobytes each, and download the batch. That size looks completely normal on screen and lets a set of ten fit comfortably inside typical attachment limits.
Why is my email rejected when the attachments are under the limit?
Because attachments are encoded for transport in a way that inflates them by roughly a third, and the message body counts too. A limit stated as 20MB accommodates noticeably less than 20MB of actual files, so leaving a margin rather than aiming at the exact number avoids the problem.
What size should photos be for email?
A few hundred kilobytes each is generous for images that will be viewed on a screen. Attaching multi-megabyte originals sends far more resolution than any recipient will use, fills the limit quickly, and slows the download for anyone on mobile data.
Should I compress or use a file-sharing link?
Compress for a handful of images; use a link for a large set. Email is a poor transport for bulk photographs given the encoding overhead and per-message limits — a link sidesteps the limit entirely and lets the recipient choose what to download.
Are my photos uploaded when I compress them?
No. Compression runs entirely inside your browser on your own device — nothing is uploaded, stored, or logged, which means your photos are not sent anywhere until you attach them to the email yourself.
Looking for the full-featured version? Open the main Compress Image tool.
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