iCloud Mail's limit is 20 MB

Apple handles it for you. When a message is bigger than your provider allows, Mail asks whether to send the attachments with Mail Drop. On iCloud.com you get the same question, once Mail Drop is turned on in Mail's settings.

Past 5 GB, Mail Drop can't help. The recipient's own mail app can also have a smaller limit than yours.

Mail Drop is Apple's way round it, and it's a good one. Attachments upload to iCloud, encrypted, and the recipient gets a link. It works from Mail on Mac, iPhone and iPad, and from iCloud.com, and the files don't use your iCloud storage.

The limits: 5 GB per email, 1 TB of Mail Drop storage at a time, and 30 days for the recipient to download before the attachment expires.

For files over 5 GB, or when you'd rather not wait for an upload, use download.fyi. Drop the file, paste the link into your email, and it streams straight from your Mac or iPhone to them.

A live link works while your page is open. For something closer to Mail Drop, a pass keeps the file online for 14 days (up to 100 GB, $5) or 30 days (up to 500 GB, $9), paid once.