Compress photos for email
A phone shoots 4 MB photos and email caps messages at 10–25 MB — three pictures and the message bounces. Drop the whole batch here: every photo is compressed to your per-file budget in the browser, and the batch comes back as individual files or one ZIP that fits the limit with room to spare.
- Nothing is uploaded
- Budget: 500 KB per photo
- HEIC · JPG · PNG · WebP
- Unlimited & free
Drop your photos here
or paste from the clipboard · ⌘V / Ctrl+V works too
JPG · JPEG · PNG · WebP · AVIF · HEIC · GIF · BMP — no file count limit
Compression settings
Applied to every imageAuto measures each image: it encodes a test pass at several quality levels, scores the result against the original, and keeps the smallest file that still clears a ~40 dB fidelity floor.
Advanced options
Auto applies a halo-free unsharp mask only when an image is scaled below 82%.
Generated in your browser by a synth — no audio file is downloaded, and it stays silent when a batch finishes in a couple of seconds.
WASM codecs are fetched from a public CDN on first use and give slightly smaller files. Every fallback still works offline.
Results
The math that makes email photos bounce
Attachment limits are about the whole message, not each file — and there is a hidden multiplier most people never see:
| Mail system | Headline limit | Safe budget after encoding |
|---|---|---|
| Gmail | 25 MB | ≈ 18 MB of files |
| Outlook.com / Microsoft 365 | 20 MB | ≈ 15 MB of files |
| Typical corporate Exchange | 10 MB | ≈ 7 MB of files |
| Strict legacy or hosted mail | 5 MB | ≈ 3.5 MB of files |
The gap exists because mail servers re-encode attachments as base64 text during transport, which inflates them by roughly 33%. That is why a "24 MB" batch can still be rejected by a "25 MB" Gmail account. The safe play is to plan against the third column.
Two dials, one batch
For email there are only two decisions, and this page pre-sets both:
- Per-photo budget: 500 KB. Big enough that a photo stays crisp on any screen a recipient will use; small enough that a dozen photos fit inside even a 10 MB corporate limit. Raising it to 1 MB buys a little more zoom detail; dropping it to 250 KB squeezes in twice as many photos.
- Maximum edge: 1280 px. Email photos are viewed on screens, not printed. Capping the long edge at 1280 pixels is invisible in an email client and typically halves the bytes again. The Advanced options panel starts set to this value on this page; switch it back to "Keep original dimensions" if you need full resolution.
Twelve photos at 500 KB each come to about 6 MB — inside every limit in the table above, including the strict ones. The results panel shows the running total as the batch processes, so there is no guessing before you attach.
iPhone photos, without the export dance
Modern iPhones save HEIC by default, and many recipients on older Windows machines or Android phones cannot open it. The usual advice — change a settings toggle, export each photo through the share sheet — is a five-step detour per batch. Here you drop the HEIC files in directly: they are decoded in the browser, compressed to the budget, and returned as JPG or WebP that everyone can open. One pass, no settings changes, and the originals on your phone are untouched.
Related pages
Sending one photo with a hard size cap instead? Use compress an image to 200 KB or compress an image to 100 KB. Preparing photos for a website rather than an email? The main compressor measures each image and picks settings automatically.
Frequently asked questions
What is the email attachment size limit?
Gmail allows 25 MB per message in total, Outlook.com and Microsoft 365 typically 20 MB, and many corporate Exchange servers cap far lower, often around 10 MB. Note that email systems also encode attachments during transport, adding roughly a third to the file size — so aiming for about three quarters of the official limit is the safe play.
How many photos can I fit in one email?
Do the division against a safe budget, not the headline limit. With a conservative 15 MB budget and every photo compressed to 500 KB, twelve photos fit comfortably; compressed to 1 MB each, about ten still do. The tool shows the running total as each file finishes, so you can see exactly what the batch will weigh.
Does it work with iPhone HEIC photos?
Yes. Drop HEIC files straight from the camera roll — they are decoded, compressed and handed back as JPG, WebP or AVIF that every email client and recipient can open, without the extra step of exporting them first.
Should I send the photos individually or as a ZIP?
Either works — the compressed files can be downloaded individually or as one tidy ZIP. A single ZIP is easier to attach and keeps some corporate filters that flag many attachments happier; individual files are friendlier for less technical recipients who just want to tap and view.
Will the photos still look good after compression?
Yes, because the engine works from a measured fidelity floor rather than a fixed preset: it encodes test passes, scores each result against the original, and keeps the smallest file that stays above roughly 40 dB PSNR — the point where differences stop being visible on a phone or laptop screen. Email is exactly the use case this quality level was tuned for.
Are my photos uploaded to a server?
No. This is a static site with no upload endpoint. Your photos are decoded, resampled and re-encoded inside your own browser, so they cannot leave your device even by accident.