Compress an Image for Email
The reply nobody wants: “your message couldn’t be delivered, the attachment is too large.” Nearly always it’s a phone photo, where one image can run 5 MB to 15 MB. Drop it below, set a target, and you get the highest quality that comfortably clears any inbox. It all happens in your browser, so the photo is never uploaded.
Free, no signup, no watermark. If a target can’t be reached, we tell you exactly why and what to change.
The real limit is smaller than the one they advertise
Gmail lists a 25 MB cap and Outlook around 20 MB, but those numbers mislead. Email encodes every attachment in a format called base64, which inflates it by roughly a third on the wire. So Gmail’s real ceiling sits closer to 18 MB, Outlook’s closer to 14 MB, and plenty of company mail servers reject anything over 10 MB before it ever reaches the other person.
One more catch: the smaller of the two limits wins. Your message has to satisfy both your provider and the recipient’s. That is why an email that sends fine to one friend bounces back from someone on a stricter corporate system. The reliable move is to keep the whole message well under 10 MB, and a compressed photo gets you there with room to spare.
How small to make it, without wrecking the photo
A photo on a screen needs far fewer kilobytes than the camera saved, because the file encodes detail no screen ever renders. For a single image, 1 MB is generous: it looks identical at viewing size and sails through any inbox. The default target below is set there for exactly that reason.
Sending several at once? Do the arithmetic the mail server does: ten photos at 1 MB each is 10 MB of attachments, right at the wall. Aim each one at 500 KB instead and the whole batch stays comfortably deliverable. The cards above jump straight to the target that fits your situation.
When compressing is the wrong answer, and we will say so
Compression shrinks photos beautifully. It cannot work miracles on everything. A 300 MB video or a folder of raw camera files will never fit in an email no matter how hard you squeeze it, and pretending otherwise would only waste your time.
For those, skip the attachment entirely: upload the file to Google Drive, OneDrive, Dropbox, or WeTransfer and paste the share link into your email. On a Mac, Apple’s Mail Drop does this for you automatically. And if what you are sending is a document rather than a photo, the compress-PDF tool is the one you want, or turn a stack of photos into one tidy attachment with photos to PDF.
Private by architecture, not by promise
Your files are processed entirely on your own device — they are never uploaded to us or anyone else. We couldn’t see them if we wanted to. This website is served from servers in the United States (North Carolina).
Processed on your device
The compression engine is JavaScript running in your browser. There is no upload step in the code — nothing to trust, just how it works.
No signup, no watermark
Every tool is free and works instantly. No account, no email required, no marks on your files.
Honest results
If your target size can’t be reached at acceptable quality, we say so and tell you exactly what to change — not silently degrade your file.
Frequently asked questions
What is the real size limit for email attachments?
Gmail advertises 25MB and Outlook about 20MB, but encoding inflates attachments by roughly a third, so the practical ceilings are closer to 18MB and 14MB. Many corporate mail servers cap incoming mail at 10MB. Because the stricter of the sender’s and recipient’s limits applies, keeping the whole message under 10MB is the dependable target.
How small should a photo be to email it?
For a single photo, 1MB looks identical on screen and clears any inbox. If you are attaching several, aim for about 500KB each so the combined size stays well under the limit.
I need to send several photos at once. What should I do?
Compress each to around 500KB, or combine them into one PDF with the photos-to-PDF tool so the recipient gets a single, ordered attachment instead of a dozen separate files.
My file is a video or a huge folder. Will compressing help?
No, and we will not pretend it will. Large videos and raw-file sets cannot be squeezed into an email. Upload them to Google Drive, OneDrive, Dropbox, or WeTransfer and email the link instead.
Is my photo uploaded in order to compress it?
No. The compression runs entirely in your browser using JavaScript. Your photo never leaves your device and is never sent to us or anyone else.
It is a PDF, not a photo. Where do I go?
Use the compress-PDF tool, which shrinks document files to a target size the same private way. If you only need to email it, getting the PDF under 1MB is plenty for most inboxes.