How upload speed is measured
After the download test, your browser sends blocks of data to Cloudflare’s servers, starting small and growing to 50 MB per request. Each upload is timed, and the result is a high percentile of those measurements, the same method as for download. While it uploads, the test also keeps measuring ping, to see how much delay builds up when your upload is busy.
What upload speed affects
| Activity | Typical upload use |
|---|---|
| Video call, 720p, one-to-one | About 1.2 Mbps (Zoom) |
| Group video call, 1080p | About 3.8 Mbps (Zoom); up to 4 Mbps for best quality (Microsoft Teams) |
| Live streaming yourself | Depends on platform and quality; several Mbps for 1080p |
| Cloud backup and photo sync | Uses as much as it can get, often for hours |
| Sending large files | No fixed need; more speed means shorter waits |
The trap with upload is that a backup or photo sync running quietly on one device can use all of it. When upload is full, everyone’s calls suffer and ping goes up for everything, including downloads.
Why upload is often so much lower
Cable and DSL networks divide their capacity unevenly, giving most of it to download. A cable plan with 300 Mbps download might offer only 10–35 Mbps upload. Many fiber plans are symmetric, offering the same speed both ways. Check your plan details or, in the U.S., the provider’s broadband label for the typical upload figure.
How long uploads take
| Upload speed | Time |
|---|---|
| 5 Mbps | About 4.4 hours |
| 20 Mbps | About 67 minutes |
| 100 Mbps | About 13 minutes |
| 500 Mbps | About 2.7 minutes |
If your upload is lower than expected
- Pause cloud backups and sync apps on every device, then test again.
- Test on a cable. WiFi upload is often weaker than WiFi download, especially from phones and laptops far from the router.
- Check your plan’s upload figure. The result may be normal for your plan.
- If upload is fine at night but poor in the evening, it may be congestion. Note the times and contact your provider.