Guide · Updated October 8, 2026
Mbps vs MB/s: What Is the Difference?
Mbps means megabits per second and MB/s means megabytes per second. There are 8 bits in a byte, so divide Mbps by 8 to get MB/s. A 100 Mbps connection downloads at most about 12.5 MB/s.
Mbps to MB/s conversion
| Internet speed | Best-case download speed |
|---|---|
| 10 Mbps | 1.25 MB/s |
| 25 Mbps | 3.1 MB/s |
| 50 Mbps | 6.25 MB/s |
| 100 Mbps | 12.5 MB/s |
| 300 Mbps | 37.5 MB/s |
| 500 Mbps | 62.5 MB/s |
| 1,000 Mbps (1 Gbps) | 125 MB/s |
Real downloads are usually a little slower because of overhead, Wi-Fi and the server you download from.
How long downloads take
Time is the file size in megabits (GB × 8,000) divided by your speed. At the best case:
| File size | 25 Mbps | 100 Mbps | 500 Mbps | 1 Gbps |
|---|---|---|---|---|
| 1 GB | 5 min | 80 sec | 16 sec | 8 sec |
| 10 GB | 53 min | 13 min | 2.7 min | 80 sec |
| 50 GB | 4.4 hours | 67 min | 13 min | 6.7 min |
| 100 GB | 8.9 hours | 2.2 hours | 27 min | 13 min |
Why are there two units?
Internet providers advertise speed in bits per second, which gives bigger numbers. Computers and browsers show file sizes and download speeds in bytes. The capital B for bytes and lowercase b for bits is easy to miss, which is why people think their downloads are eight times slower than advertised.
Quick rules
- Capital B = bytes. Lowercase b = bits.
- Mbps ÷ 8 = MB/s. MB/s × 8 = Mbps.
- 1 GB = 1,000 MB (decimal), and about 8,000 megabits.
To see how fast your own connection is, run the speed test. For monthly data, use the data usage calculator.
Frequently asked questions
Is Mbps the same as MB/s?
No. Mbps is megabits per second and MB/s is megabytes per second. One byte is 8 bits, so MB/s is one eighth of the Mbps number.
How many MB/s is 100 Mbps?
100 Mbps is 12.5 MB/s in the best case.
How long does it take to download 1 GB at 100 Mbps?
About 80 seconds in the best case, since 1 GB is roughly 8,000 megabits and 8,000 divided by 100 is 80.
Why does my download show a lower number than my plan?
Your browser or app shows MB/s while your plan is in Mbps. Multiply the MB/s figure by 8 to compare them.
Related tools and guides
- Internet speed test: measure your real speed in Mbps.
- What is a good internet speed?: tiers from basic to excellent.
- Data usage calculator: estimate monthly data in GB.
- How to read a speed test: what each number means.