Units
Download
How to use
Basic use
Enter a value followed by a symbol (e.g. 15 Mb, 1.5 GB or 47 GiB) to see its equivalents in bits and bytes in the SI and IEC systems. Decimals with a point or a comma are accepted (a lone separator is always read as a decimal: 1,000 GB is 1 GB). Autocomplete suggests valid symbols as you type.
Bits and bytes
Tell apart b (bit, lowercase) and B (byte, uppercase): 1 B = 8 b. The Common section shows the total in bits and in bytes.
SI vs IEC
The SI prefixes (kB, MB, GB...) use powers of 1000; the IEC prefixes (KiB, MiB, GiB...) use powers of 1024 per the IEC 80000-13 standard. So 1 kB = 1000 bytes but 1 KiB = 1024 bytes.
Download time
The Download tab calculates how long an amount takes to transfer at a given speed (e.g. 100 Mb/s, 300 Mbps or 12 MB/s), and shows that speed in the units your provider (Mb/s) and your browser (MB/s, MiB/s) use. Mind the capital letter: Mbps is megabits and MBps megabytes, eight times more. Efficiency is the % of the advertised speed a real download uses (90 % by default). The typical connections buttons fill in the speed, and below you see how long a photo, a movie or a game would take. With “I want it to take” it works backwards: what speed you need.
