System Grab Bag

Unit Converter for File Sizes

This converter converts sizes of different types of size types used in computing. For example, this will convert between megabytes to gigabytes or gigabytes to megabytes, terabytes to petabytes and more.
This tool also allows you to set the amount of bits per byte, which is useful for some (albeit rare) systems that don't have a 8-bit byte.

Converting 25745831615488.0 bits to KB, MB, GB, TB, PB, and more

Assuming a bit byte
Bits Bits (-1000 | -100 | -10 | -1 | +1 | +10 | +100 | +1000)
Bytes B (-1000 | -100 | -10 | -1 | +1 | +10 | +100 | +1000)
Kilobytes KB (-1000 | -100 | -10 | -1 | +1 | +10 | +100 | +1000)
Kibibytes KiB (-1000 | -100 | -10 | -1 | +1 | +10 | +100 | +1000)
Megabytes MB (-1000 | -100 | -10 | -1 | +1 | +10 | +100 | +1000)
Mebibytes MiB (-1000 | -100 | -10 | -1 | +1 | +10 | +100 | +1000)
Gigabytes GB (-1000 | -100 | -10 | -1 | +1 | +10 | +100 | +1000)
Gibibytes GiB (-1000 | -100 | -10 | -1 | +1 | +10 | +100 | +1000)
Terabytes TB ( -1 | +1 | +10 | +100 | +1000)
Tebibytes TiB ( -1 | +1 | +10 | +100 | +1000)
Petabytes PB ( +1 | +10 | +100 | +1000)
Pebibytes PiB ( +1 | +10 | +100 | +1000)
8-bit chunks (octets)
16-bit chunks (hextets)
32-bit chunks
64-bit chunks
128-bit chunks
  1. 25745831615488 bits
  2. 3218228951936 bytes (8-bit bytes)
  3. 3218228951.936 KB
  4. 3142801710.875 KiB
  5. 3218228.951936 MB
  6. 3069142.295776367 MiB
  7. 3218.228951936 GB
  8. 2997.2092732191086 GiB
  9. 3.218228951936 TB
  10. 2.9269621808780357 TiB
  11. 0.003218228951936 PB
  12. 0.0028583615047637068 PiB
  13. 3218228951936 8-bit chunks (octets)
  14. 1609114475968 16-bit chunks (hextets)
  15. 804557237984 32-bit chunks
  16. 402278618992 64-bit chunks
  17. 201139309496 128-bit chunks

Some things to try

What are these different types of sizes?

In particular, what is a kebibyte, mebibyte, etc? It does sound made up. But these prefixes are used to resolve historical differences between usage of the "kilo" prefix as used in other weights and measures (such as kilogram), which means 1000, and computing (especially with rerference to computer memory) which generally uses 1024. This was parodied by xkcd 394, which has a humorous table of different so-called kilobyte standards and included a table which is also included below (but don't use it as a reference :))

Symbol Name Size Notes
kB Kilobyte 1024 or 1000 bytes 1000 bytes during leap years, 1024 otherwise
KB Kelly-Bootle Standard Unit 1012 bytes Compromise betweeen 1000 and 1024 bytes
KiB Imaginary Kilobyte 1024√-1 bytes Used in Quantum Computing
kB Intel Kilobyte 1023.937528 bytes Calculated on Pentium FPU
Kb Drivemaker's Kilobyte Currently 908 bytes Shrinks by 4 bytes each year for marketing reasons
KBa Baker's Kilobyte 1152 bytes 9 bits to the byte since you're such a good customer

Base 10 (1000 bytes = 1 kilobyte)

This definition is generally used by drive manufacturers and is the standard SI unit for a kilobyte. It's used in data transfer rates and some other things. The advantages of it is that it's a SI unit, so it's likely to be understood. Some disadvantages include that it is inconsistent with how computer memory is reported (using base 2 instead) and it is inconsistent with some popular operating systems. This page uses the SI prefixes, disambiguating by using the "kibi" suffixes.

Using this definition, the size that you entered is 3218228951.936 kilobytes.

Base 2 (1024 bytes = 1 kilobyte)

Another popular contender is to use base 2 (i.e. 1024 bytes in 1 kilobyte). This is commonly used by memory manufactuers, CPU cach sizs, etc (due to the heavy use of binary addressing), and some telecommunications companies, and probably most importantly, Microsoft Windows. Because this page uses the SI prefixes, we disambiguate with the kibi suffix. However, as xkcd has again pointed out...

I would take 'kibibyte' more seriously if it didn't sound so much like 'Kibbles N Bits'.

In addition, many older computers report using powers of 2. Many tools on Linux, such as top, report using the "kibi" suffix.

Using this definition, the size that you entered is 3142801710.875 kilobytes.

How big is a byte?

8 bytes, generally. This is de facto standard, but some computers, particularly older computers, used a different byte size. Many 6-bit of 9-bit computers were used in the 1960s to store characters and byte sizes could be anywhere from 2 to 3 to 4 to 8 to 10. The term octet refers unambiguously to a grouping of 8 bits, and can be seen today in some media types such as application/octet-stream.