Image Compressor
Drag the quality slider and watch the file size shrink in real time.
Drop images to compress
or click to browse, or paste with Ctrl/Cmd+V — drop several at once to process a whole batch
Preview
Compression settings
Type a budget and the tool searches for the highest quality that fits, in at most eight encodes.
Batch queue
Attachment limits are smaller than the number you were told
Gmail advertises 25 MB and Outlook.com 20, but the number that actually decides whether your mail arrives is the smallest limit anywhere on the path — and corporate Exchange servers very commonly cap incoming mail at 10 MB, with plenty sitting at 5. You do not control the receiving end, which is why five megabytes is the budget this page defaults to: it is the figure that gets through essentially everywhere.
There is a second reason the advertised limit misleads. Attachments are MIME-encoded in transit, which inflates them by about a third, so a 20 MB pile of photos is roughly 27 MB on the wire and bounces off a 25 MB limit. Budgeting against the raw file size with room to spare is the only way to be sure.
If you are sending several photos, use the batch queue rather than doing them one at a time. The target applies per file, so each photo gets its own quality search rather than one setting applied blindly to all of them, and the copyable summary at the end gives you the total to paste into the mail itself.
How to compress an image to Email
- Drop your image on the panel above — or paste it, or drop a whole folder to do the lot at once.
- The Email budget is already set. Change it if you need something different.
- The tool searches for the highest quality that fits and tells you what it settled on and how many encodes it took.
- Drag the divider across the preview to see the original against the result, and switch to 1:1 zoom to judge the artifacts at real pixel scale.
- Download. Nothing was uploaded at any point — the whole thing ran on your own machine.
Questions
What size should an email attachment be?
Aim for 5 MB or less for the whole message. Gmail and Outlook allow far more, but corporate mail servers frequently cap incoming mail at 10 MB or even 5, and the smallest limit on the path is the one that decides.
Why does my 20 MB of photos bounce off a 25 MB limit?
Because attachments are encoded for transit, which inflates them by roughly a third. Twenty megabytes of files is about twenty-seven megabytes of email. Budget against the raw size with room to spare.
