Someone forwards you a dozen photos from a camera roll, you try to email them along, and the message just... doesn't send. Or it sends, then sits in the recipient's inbox for three minutes chewing through their data. This happens constantly, and it's almost always a resolution problem rather than an email problem.
Most email providers cap total attachment size somewhere between 20 and 25 MB per message. Sounds like plenty, until you remember a single modern phone photo can be 4–8 MB on its own. Attach six of those and you've blown past the limit before you've written a word of the actual email.
The fix isn't fewer photos, it's smaller ones
Most people don't need email attachments at full camera resolution — whoever's receiving them is going to view them on a phone or laptop screen, not print them at poster size. Resizing each photo down to around 1600px on the longest edge, then compressing to a reasonable JPEG quality, typically brings a 5 MB photo down to somewhere around 300–600 KB with no visible loss on a screen.
A recipient opening your email on mobile data is going to notice a slow-loading attachment far more than they'll ever notice it was 1600px instead of 4000px.
A realistic example: six vacation photos averaging 5 MB each comes to 30 MB total, already past most attachment limits on its own. Resized and compressed the same way, those same six photos usually total somewhere around 2–3 MB combined — comfortably under any provider's limit, and noticeably faster to send and receive on both ends.
Depends what you're sending them for
Just sharing memories with family? 1600px wide, JPEG, moderate compression, done. Sending for someone to edit or print later? Keep more resolution, but still compress — there's rarely a good reason to send a fully uncompressed file over email regardless. Attaching to a work email with a strict size policy? Check whether there's a hard KB limit first (some corporate systems still cap attachments quite tightly) and target under that number specifically, not just "smaller than before."
The habit that actually saves time: resize and compress before you open the email client, not after you've already hit "too large to send." Batch it for everything you're about to share at once, rather than doing it one photo at a time mid-email while people wait.
ImgReduce's file-size mode is built for exactly this — set a target like 300 KB and it does the rest.