How to use the speed unit converter
Bits vs bytes: the one idea that explains everything
Network speeds are measured in bits per second (Mbps). File sizes are measured in bytes (MB, GB). 1 byte = 8 bits, so to turn a line speed into a file speed, divide by 8: 100 Mbps ÷ 8 = 12.5 MB/s. Going the other way, multiply by 8.
Per-hour and per-day figures
MB/s × 3,600 seconds = MB per hour. That is how a 'fast' line can still have a data budget: leave a 100 Mbps line running flat out and it moves about 45 GB every hour.
Example
100 Mbps = 12.5 MB/s = 45 GB per hour. And 1 Gbps = 125 MB/s. If a speed test says 72 Mbps, expect downloads around 9 MB/s — that is correct behaviour, not a fault.
Frequently asked questions
Why is 100 Mbps only 12.5 MB/s?
Because bits and bytes are different units. There are 8 bits in 1 byte, so megabits per second divided by 8 gives megabytes per second: 100 ÷ 8 = 12.5. Broadband is sold in bits; files are counted in bytes.
Is a GB 1,000 MB or 1,024 MB?
Both conventions exist. Telecom and storage sold to consumers use decimal: 1 GB = 1,000 MB. Operating systems often use binary (1 GiB = 1,024 MiB), which is why a '500 GB' drive shows as about 465 GiB. This converter uses the decimal convention, like your ISP.
How fast is gigabit broadband in real terms?
1 Gbps = 1,000 Mbps = 125 MB/s — about 450 GB per hour at full speed. In practice, Wi-Fi, servers and overhead mean you will rarely sustain the full rate.
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