You have a 100 Mbps internet package, but when downloading files, you see a value of around 12 MB/s on the screen. At first glance, you may think that your connection is far below the promised speed. However, if your internet provider shows the speed in megabits and your download application shows the speed in megabytes, comparing the two numbers directly will lead to the wrong conclusion. You don’t need to change the modem setting to notice this difference.
The theoretical equivalent of 100 Mbps is 12.5 MB/s. Because a byte consists of eight bits and to convert megabits/second to megabytes/second, it is necessary to divide by eight. For example, 80 Mbps corresponds to 10 MB/s. Vodafone’s guide to speed units uses the same conversion.
What is the difference between Mbps and MB/s?
Lowercase “b” means bit, uppercase “B” means byte. Mbps is the amount of megabits transferred per second; MB/s indicates the amount of megabytes transferred per second. Therefore, MB/s is also a unit of speed, only if it says MB, we are talking about the file size or amount of data. If you encounter the notation MBps, it means the same thing as MB/s.
There is another distinction here: MB and MiB do not refer to the same size. According to NIST’s table of units, 1 MB is 1,000,000 bytes; 1 MiB is 1,048,576 bytes. Therefore, the equivalent of 100 Mbps is 12.5 MB/s, which is approximately 11.92 MiB/s. If your application shows MiB/s, you should not consider this small numerical difference as connection loss.
How many MB per second is your internet speed?
The table below shows the theoretical equivalents calculated by dividing the Mbps value by eight. The last column contains the times based on the uninterrupted transfer of a 10 GB file at this speed. In the account, 1 GB is considered as 1,000 MB; Additional data traffic and waits on the network are not taken into account.
| connection speed | Theoretical equivalent | Ideal time for 10 GB |
|---|---|---|
| 16Mbps | 2MB/s | 1 hour 23 minutes 20 seconds |
| 35Mbps | 4.375MB/s | Approximately 38 minutes 6 seconds |
| 50Mbps | 6.25MB/s | 26 minutes 40 seconds |
| 100Mbps | 12.5MB/s | 13 minutes 20 seconds |
| 200Mbps | 25MB/s | 6 minutes 40 seconds |
| 500Mbps | 62.5MB/s | 2 minutes 40 seconds |
| 1000Mbps | 125MB/s | 1 minute 20 seconds |
For your own file Divide the size in MB by the download speed in MB/s and you can find the time in seconds. For example, a 2,000 MB file downloads in 200 seconds with an average speed of 10 MB/s, that is, 3 minutes and 20 seconds. If the download speed changes, the result also changes. Therefore, it is more meaningful to use the average speed you see throughout the download instead of the upper limit of your package when calculating the practical time.
Unit difference or actual slowness? How to check?
First read the unit shown by the app, then convert the speed to the same unit. For example, on a 100 Mbps connection, 11 MB/s corresponds to approximately 88 Mbps file transfer; 2 MB/s equals 16 Mbps. In the second case, you cannot explain the difference only by distinguishing between bits and bytes. However, the download speed of a single file does not prove that the problem is directly caused by your internet provider.
- Pause background traffic. Temporarily stop other downloads and cloud backups. Also check for heavy data transfer on devices using the same connection. This way you can reduce sharing of connection capacity during measurement.
- Run a speed test on the same device. Measure the result with a service like Fast.com and note the unit on the screen. Repeat the test at different times, with another speed testing service as needed. Fast.com transfers data with Netflix servers to estimate the speed the connection can deliver.
- Compare wired and wireless results. If possible, connect the computer to the router with a suitable Ethernet connection and measure again. If you get low results over Wi-Fi and high results over cable, check the wireless connection conditions. Also take into account the speed limit of the network port and adapter in wired testing.
- Compare testing with file transfer. Find the MB/s equivalent by dividing the result you measured in Mbps by eight. Check if there is a speed limit on the downloading app and compare it with downloading from another reliable source. A decrease seen in only one service indicates that the transfer conditions of that service should be examined separately.
The wireless speed value on the router’s box does not indicate the speed of your internet subscription. According to TP-Link’s official statement, the connection speed between the device and the router and the internet speed are different; The slowest segment on the network may limit transmission. For example, a 100 Mbps WAN port cannot provide internet transfer over 100 Mbps, even if it writes higher values on the wireless side.
At the end of the check, see how well your download speed matches the measurement converted to the same unit. If the speed is constantly below expectations in different services and repeated tests, you can record the results, test hours and connection type and share them with your internet provider. Don’t forget to restart any downloads and backups you paused for testing. Don’t think that your connection is eight times slower just because of the difference between Mbps and MB/s.