Resize and compress images for email attachments

Most email providers soft-limit attachments at 10-25 MB, but recipients on mobile will struggle with anything over 1-2 MB per image. Phone photos today are often 4-8 MB each. If you attach several of them, you are filling someone's inbox and making them wait on a slow connection. Here is the fastest way to fix that before you hit send.

The two-step approach

Step 1 - Crop out what is not needed

If the photo has dead space, background clutter, or margins your reader does not need to see, trim it first. Open Image crop, drop your photo, and select the region that actually matters. A tighter crop means fewer pixels to encode, and the result looks more intentional rather than just compressed.

Step 2 - Compress to the target size

Drop the cropped image into Image compress. Switch the format to WebP or JPEG and lower the quality slider until the file size drops below your target. For most email use, 500 KB to 1 MB per image is a safe range - sharp enough to read clearly on screen, light enough not to clog an inbox.

Target sizes by use case

Why not just send the original?

• Slow to upload on your end and slow to download on theirs - especially on mobile data.
• Gmail and Outlook sometimes auto-compress or strip oversized images, producing worse quality than if you had controlled the output yourself.
• Large attachments can trigger spam filters on some corporate mail servers.
• Storage fills up quickly when a thread has several high-resolution photos attached.

Which format is best for email?

JPEG is the safest and most widely supported. Every email client, every device, and every operating system knows how to render it. WebP produces smaller files but is not supported in older Outlook versions on Windows, so if you are unsure about your recipient's setup, JPEG is the reliable choice.

Taking 30 seconds to compress before sending solves the problem cleanly without affecting the visible quality of your images.