How to convert bits, bytes, KB, MB, GB and TB

Type or paste a size into any of the six fields and the other five follow as you edit; there is no Convert button, and the field you are typing in is never reformatted under your cursor. One byte is eight bits, and the KB, MB, GB and TB rows step by 1,024, the convention file managers and memory sizes use.

The conversion runs in this browser. No value is sent to a server, the page keeps working offline, and nothing you type is stored.

  1. Click one of the six fields and type a number, or paste one from a file listing or a log.
  2. Read the other five rows: bit, byte, KB, MB, GB and TB are filled in at the same time.
  3. Empty the field to clear the whole row, or press Reset all to empty all six fields and start again.
  4. Type into a different field to convert from that unit instead - the six rows always describe one size, not six independent ones.
  5. If the input cannot be read, the line under the fields names the reason: a comma used as decimal separator, letters, a negative number, or a value too large to convert.

Units, precision and limits

Units and the 1,024 step

bit and byte are exact: 1 byte = 8 bits. Above that the page counts in powers of 1,024, so 1 KB = 1,024 bytes, 1 MB = 1,024 KB, and 1 TB = 1,024 GB. This is the convention file managers use for file sizes and memory. The decimal SI version of the same prefixes (1 kB = 1,000 bytes) is not offered, so a drive sold as 1 TB holds 1,000,000,000,000 bytes and reads here as 0.909494701772928 TB.

Only these six units have a row. PB and EB cannot be selected, but any number can be typed, so a size given in gigabytes converts to terabytes just as well.

Precision and rounding

Results carry up to 15 significant digits and switch to exponent notation below 0.000001 and at 10^15 and above, so one bit reads as 1.13686837721616e-13 TB instead of a long row of zeros. Integers up to 9,007,199,254,740,991 (2^53 - 1) convert exactly. A longer number is rounded by the browser to the nearest value it can hold before it is converted, and the page says so under the fields.

The field you type in keeps exactly what you wrote; only the other five are rewritten, so results never interfere with the digits you are entering.

What the page does not do

There is no SI (1,000-based) switch, no per-second rate, no history and no upload; the page converts the six units above and nothing else. The result is only as precise as the number you type, and a size quoted by a provider may include overhead this converter cannot know about.

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