How to compress photos for email (no upload)

Photo file sizes tripled in the last five years; email attachment limits didn't move. Here are the four ways to compress photos for email: sorted by how much friction each one carries.

Method 1: EmailPhotos.com (browser-side, recommended)

A purpose-built compressor that runs entirely in your tab:

1. Open EmailPhotos.com.
2. Drag photos in (or tap to pick).
3. Wait a beat: each photo compresses in a Web Worker.
4. Press Send or Download zip.

The engine balances quality across all the photos so the total stays under your chosen budget (default 14 MB; toggleable to 22 MB for Gmail- only). EXIF and GPS are stripped by default. Works on iPhone, Android, Mac, Windows and Linux.

Method 2: macOS Preview

If you only have one or two photos and you're on a Mac:

1. Open the photo in Preview.
2. Tools → Adjust Size… Set "Width" to 2000 px (uncheck "Resample image" if you only want quality reduction without resizing).
3. File → Export… Choose JPEG, slide quality to about 70 %.

Repeat per photo. Fine for a few, painful for ten.

Method 3: iPhone Mail's built-in resize

When you attach photos in the iOS Mail app, a size picker appears at the top of the compose window:

• Small: about 100 KB each. Recipients see a thumbnail.
• Medium: about 500 KB. Reasonable on a phone screen.
• Large: about 1 MB. Looks good on most laptops.
• Actual Size: original. Use this only with one or two photos.

Convenient when you're already in Mail. Doesn't cover videos and isn't available in Gmail or Outlook for iOS.

Method 4: online compressors (with caveats)

Sites like TinyPNG, iLoveIMG and CompressJPG do the job, but they all upload your photos to a third-party server. That's fine for a meme, less fine for family pictures. Check each tool's privacy policy. If you'd rather not upload, EmailPhotos.com is the local alternative.

How much should I compress?

The cleanest mental model is "good enough on a screen". JPEG at quality 0.8 with a 2560 px long edge is the rule-of-thumb: visually identical to the original on a phone or laptop, but typically 4× smaller.

EmailPhotos.com's Auto quality picks a starting point based on your budget and the number of photos, then iterates per file. For a typical 10-photo batch in a 14 MB budget, it lands around quality 0.78 with a 2400 px long edge.

What about HEIC?

iPhones shoot HEIC by default. The format is great: 30 % smaller than JPEG at the same quality: but most email clients (Outlook, Yahoo, older Apple Mail) can't display it. The reliable answer is to convert to JPEG before sending.

Safari decodes HEIC natively. Chrome and Firefox don't, so any tool you pick needs a fallback. EmailPhotos.com lazy-loads a WebAssembly HEIC decoder only when needed; the rest of the pipeline doesn't change.