Email gives up somewhere around 20 or 25 MB, and a single phone video can be ten times that. The fix is nearly always one of two things: send a link instead of an attachment, or make the file smaller before it goes. Below are the free limits for the services you probably already have, how long uploads really take, and real measurements of which files shrink when you zip them. Spoiler: photos and video don't.
Email was designed for text, and attachments ride along encoded as text. That encoding inflates a file by roughly a third, which is why a 20 MB video can bounce off a 25 MB limit. Most providers cap the total message somewhere between 10 MB and 25 MB, and the recipient's server has its own cap that you can't see. Our guide to email attachment size limits has the provider-by-provider numbers and the encoding math.
Anything past about 15 MB, stop fighting the attachment limit. Either send a link, or make the file smaller. Often the answer is both.
Upload the file somewhere and send a link. You probably already have a service that does this, built into your email account. Here's what the common free options allow, from each provider's own help pages as of October 2026:
| Method | Free limit | Worth knowing |
|---|---|---|
| Gmail attachment | 25 MB | Larger files are swapped for a Google Drive link automatically |
| Outlook.com attachment | 20 MB | Counts the message text too; bigger files go via OneDrive |
| Google Drive (free) | 15 GB storage | Shared with Gmail and Photos; link sharing, no expiry |
| OneDrive (free) | 5 GB storage | Link sharing; expiry and passwords need a paid plan |
| iCloud Mail Drop | 5 GB per message | Recipient gets a download link that lasts 30 days |
| WeTransfer (free) | 3 GB per 30 days | Up to 10 transfers in that rolling window |
| Dropbox Transfer (Basic) | 2 GB per transfer | Links expire after 7 days |
| Signal | 100 MB per attachment | End-to-end encrypted; fine for documents, not raw video |
| USB stick formatted FAT32 | 4 GB per file | Reformat as exFAT for bigger single files |
For a one-off file to someone outside your organization, a transfer service like WeTransfer or Dropbox Transfer is the least fuss: the recipient doesn't need an account, and the link expires on its own. For anything you'll update or share with the same people again, a cloud drive folder is better, because you send the link once and keep replacing the contents.
Upload speed is usually the bottleneck, and it's often far slower than your download speed. Cable plans commonly upload at a tenth of their download rate. These times assume you get the full speed, which you won't on busy Wi-Fi:
| File size | 10 Mbps | 50 Mbps | 100 Mbps | 500 Mbps |
|---|---|---|---|---|
| 100 MB | 1.3 min | 16 sec | 8 sec | 2 sec |
| 1 GB | 13.3 min | 2.7 min | 1.3 min | 16 sec |
| 5 GB | 1.1 hours | 13.3 min | 6.7 min | 1.3 min |
| 20 GB | 4.4 hours | 53 min | 27 min | 5.3 min |
The math is simple: multiply megabytes by 8 to get megabits, then divide by your upload speed. A 5 GB video over a 10 Mbps connection is 40,000 megabits ÷ 10, a bit over an hour. Run a speed test before you start a big upload, plug into Ethernet if you can, and keep the laptop awake until it finishes. Browser-based uploads usually die when the machine sleeps.
Sometimes a lot, often barely at all. It depends on whether the file is already compressed. We ran real files from our own machine through deflate, the same algorithm a standard .zip uses, at its strongest setting:
| File type | Size reduction | Why |
|---|---|---|
| XML sitemap (573 KB) | 95.5% | Repetitive text compresses brilliantly |
| JSON data file (204 KB) | 84.2% | Same story: structured text |
| HTML page (17 KB) | 69.1% | Text again |
| PNG screenshots (21 files) | 14.9% median | Already compressed losslessly |
| PDFs (21 files) | 4.0% median | Most PDFs compress their own contents |
| Camera JPEGs (17 files) | 1.3% median | JPEG is already compressed |
| MP4 videos (25 files) | 0.3% median | Video codecs leave nothing to squeeze |
So zip a folder of spreadsheets, logs or CSV exports and it might shrink to a fifth of its size. Zip a folder of phone photos or videos and you'll save almost nothing. The real benefit there is packaging: one file instead of 300, which survives upload and download without anything going missing.
When zipping won't help, you need to reduce the content itself:
All three of our tools run in your browser, so the file isn't uploaded to us while you shrink it.
A shared link is only as private as the link itself. Anyone who has it can usually open the file, and links get forwarded, pasted into chats and indexed by mail scanners. A few habits close most of the gaps:
For a one-off file, a transfer service such as WeTransfer (3 GB free) or Dropbox Transfer (2 GB free) is simplest because the recipient needs no account. For bigger files, upload to Google Drive (15 GB free) or OneDrive (5 GB free) and share a link.
You can't attach it directly in most email services. Gmail swaps it for a Google Drive link automatically, Outlook offers a OneDrive link, and Apple Mail offers Mail Drop for files up to 5 GB. Or compress the file first and see if it fits.
Only for files that aren't already compressed. In our test, text files such as XML, JSON and HTML shrank 69% to 96%, but camera JPEGs shrank about 1% and MP4 videos about 0.3%.
About 13 minutes at 10 Mbps upload, under 3 minutes at 50 Mbps and around 80 seconds at 100 Mbps. Real-world speeds are usually a bit slower than the plan's headline figure.
The drive is probably formatted as FAT32, which can't hold any single file of 4 GB or more. Reformatting it as exFAT removes that limit, but it erases the drive, so copy anything you need off it first.