What Is Kilobit (kbit)?
A kilobit is a unit used to measure small amounts of digital data. It is often used for internet speed and for sizes of very small files. A kilobit is made of many bits, and bits are the smallest pieces of data in computers.
Definition
A bit is a single piece of information. It can be 0 or 1. A kilobit is a group of bits.
There are two common ways people define a kilobit.
- Decimal kilobit used in most networking. 1 kilobit kbit or kb equals 1,000 bits.
- Binary kilobit less common. 1 kilobit equals 1,024 bits.
When you see internet speed, like 512 kbit per second, it almost always means 1 kilobit equals 1,000 bits.
History / Origin
The word kilobit comes from two parts.
- Kilo means 1,000 in the metric system.
- Bit is short for binary digit.
In early computing and telecom systems, people needed a way to talk about groups of bits without saying very large numbers. So they used metric prefixes like kilo, mega, and giga. Over time, kilobit became a common word in data communications and network speeds.
In computer memory and storage, people often used powers of 2, like 1,024. This is why some people also used 1 kilobit to mean 1,024 bits. Today, in most network and telecom uses, 1 kilobit is treated as exactly 1,000 bits.
Symbol & Abbreviation
The main symbol for kilobit is:
- kbit
Other ways you might see it written include:
- kb often used in network speed, like 256 kbps
- kbit s or kb s used for kilobits per second
Careful. A lowercase b usually means bit. An uppercase B usually means byte. So:
- kb means kilobit
- kB means kilobyte
Current Use Around the World
Kilobits are used worldwide in areas where data amounts are small or where speeds are not very high.
Common uses include:
- Internet speed Some services still show speeds in kilobits per second, written as kbit s or kbps. For example, 512 kbps.
- Old modems and lines Dial up modems and some telephone based links used kilobits to show speed.
- Small data transfers Simple sensors, smart cards, and older mobile systems may use kilobits.
Today, many modern networks use larger units like megabits Mbit and gigabits Gbit because speeds are much higher. Still, kilobit remains useful for teaching, for basic examples, and for very low speed systems.
Example Conversions
These examples use the decimal definition 1 kilobit equals 1,000 bits because this is the standard in networking.
- 1 kilobit kbit equals 1,000 bits
- 8 kilobits equal 8,000 bits
You can change between kilobits and bytes like this.
- 8 bits equal 1 byte
- 1 kilobit kbit equals 1,000 bits which is 1,000 divided by 8 equals 125 bytes
- 8 kilobits equal 8,000 bits which is 8,000 divided by 8 equals 1,000 bytes
Some more examples.
- 64 kbit equals 64,000 bits equals 8,000 bytes equals about 7.8 kB kilobytes
- 256 kbit equals 256,000 bits equals 32,000 bytes equals about 31.25 kB
- 512 kbit equals 512,000 bits equals 64,000 bytes equals about 62.5 kB
If a connection is 128 kbit per second and you download a 128 kB kilobyte file, it will take about 8 seconds in perfect conditions. This is because 128 kB equals about 1,024 kbit.
Related Units
Units smaller than a kilobit.
- Bit b the basic unit. 0 or 1.
Units larger than a kilobit.
- Kilobyte kB about 8 kilobits in the decimal system.
- Megabit Mbit or Mb about 1,000 kilobits.
- Megabyte MB about 8,000 kilobits.
- Gigabit Gbit or Gb about 1,000,000 kilobits.
- Gigabyte GB about 8,000,000 kilobits.
You may also see special binary based units, like kibibit written as Kibit, which is defined as 1,024 bits. This is different from the decimal kilobit kbit, which is 1,000 bits.
FAQs
Is a kilobit the same as a kilobyte
No. They are different. A kilobit is based on bits. A kilobyte is based on bytes. There are 8 bits in 1 byte. So in the decimal system, 1 kB kilobyte is about 8 kbit kilobits.
Why is internet speed shown in kilobits not kilobytes
Internet speed usually counts how many bits can move each second. Network equipment sends data bit by bit. So speeds are often written in bits per second, such as kbit s or Mbit s.
Is 1 kbit 1,000 or 1,024 bits
In most network and telecom uses, 1 kilobit equals 1,000 bits. Some older computer uses treated 1 kilobit as 1,024 bits. Today, to avoid confusion, many people use kbit for 1,000 bits and Kibit for 1,024 bits.
How can I change kilobits per second to kilobytes per second
First, change kilobits kbit to bits. Then divide by 8 to get bytes. Finally, divide by 1,000 to get kilobytes. You can also divide the kilobit per second value by 8 to get about kilobytes per second in the decimal system.
Do modern networks still use kilobits
Yes, but less often. Many modern broadband and mobile networks are fast and use megabits or gigabits. However, kilobits are still used in low speed links, basic devices, and in teaching examples.