# What is Mbps vs MB?

Mbps (megabits per second) measures connection speed, while MB (megabytes) measures file size, and one byte equals eight bits.

_Source: https://sharelargefilesfree.com/what-is-mbps-vs-mb · Updated 2026-10-13_

**Quick answer:** Mbps (megabits per second) measures connection speed, while MB (megabytes) measures file size, and one byte equals eight bits.

## Mbps vs MB (Megabits per second vs megabytes) explained

Mbps measures how fast data moves, while MB measures how much data there is. Internet providers advertise speeds in **Mbps**, with a small b for bits. Files are measured in **MB** or GB, with a capital B for bytes. Since a byte is eight bits, divide Mbps by 8 to get megabytes per second.

A 100 Mbps connection moves at most about 12.5 MB per second. A 1 GB file would then take roughly 80 seconds in ideal conditions, and longer in practice.

Upload speed matters most when sending. Many home connections upload far slower than they download, so check your upload figure when planning a big transfer.

## How long uploads take at different speeds

Best-case times, using 1 GB = 1,000 MB = 8,000 megabits:

| Upload speed | MB per second | 1 GB | 10 GB |
| --- | --- | --- | --- |
| 10 Mbps | 1.25 | about 13 min | about 2 h 15 min |
| 50 Mbps | 6.25 | about 2 min 40 s | about 27 min |
| 100 Mbps | 12.5 | about 1 min 20 s | about 13 min |
| 500 Mbps | 62.5 | about 16 s | about 2 min 40 s |

Real uploads are usually slower because of Wi-Fi, other devices on the network and distance to the server, so add some margin.

## Worked example: a 4 GB video on a 20 Mbps upload

1. Convert the size to megabits: 4 GB × 8,000 = 32,000 megabits.
2. Divide by the speed: 32,000 ÷ 20 = 1,600 seconds.
3. Convert to minutes: 1,600 ÷ 60 = about **27 minutes**.

If your speed test shows 20 Mbps download but only 5 Mbps upload, use the 5: the same file would take four times as long, about 1 hour 47 minutes.

## Why your computer may show a different size

Most internet speeds and many storage makers use decimal units, where 1 GB is 1,000,000,000 bytes. Windows measures in binary units, where its GB is 1,073,741,824 bytes, but still writes GB. So a file Windows calls 1 GB is about 7% bigger in decimal terms, while macOS uses decimal units. The difference is small, but it explains why sizes do not always match between devices.

## Frequently asked questions

### How many MB per second is 50 Mbps?

About 6.25 MB per second at best, because you divide by 8.

### Why is my upload slower than my download?

Many home internet plans are asymmetric, with much less upload capacity than download capacity.

### Is MB the same as Mb?

No. MB is megabytes and Mb is megabits. One megabyte is eight megabits.

### How do I find my upload speed?

Run any internet speed test and look at the upload figure, not the download figure. Test on the same Wi-Fi or cable you will use to send.