Data Size Converter
Convert KB, MB, GB and TB side by side with KiB, MiB, GiB and TiB, plus bits and bytes, and see why a 1 TB drive shows 931 GB.
Conversions
1 GB = 1,000,000,000 bytes
Counted in 1024s that is about 953.67 MiB, which Windows and similar systems show as “953.67 MB”.
Bytes and bits
- B= 8 bit
- bit= 1/8 B
Decimal (SI, × 1000 per step)
- KB= 1000 B
- MB= 1000² B
- GB= 1000³ BInput unit
- TB= 1000⁴ B
- PB= 1000⁵ B
- EB= 1000⁶ B
Binary (IEC, × 1024 per step)
- KiB= 1024 B
- MiB= 1024² B
- GiB= 1024³ B
- TiB= 1024⁴ B
- PiB= 1024⁵ B
- EiB= 1024⁶ B
Bits (common for network speeds)
- kbit= 1000 bit
- Mbit= 1000² bit
- Gbit= 1000³ bit
- Tbit= 1000⁴ bit
Copied numbers have no thousands separators.
How to use
- Enter a value and pick its unit, such as 1 TB. Each unit is labelled decimal (× 1000) or binary (× 1024).
- Bytes, bits, decimal units (KB, MB, GB…) and binary units (KiB, MiB, GiB…) are listed side by side for easy comparison.
- Adjust “Decimal places” if needed and click “Copy” on any row. Click “Example” to see what a 1 TB drive shows on a computer.
FAQ
Why does my 1 TB drive show only 931 GB?
Drive makers count in powers of 1000: 1 TB = 1,000,000,000,000 bytes. Windows counts in powers of 1024 but still writes “GB”: 1,000,000,000,000 ÷ 1024³ ≈ 931.32, so it shows about 931 GB. Nothing is missing; the correct label would be 931.32 GiB.
What is the difference between KB and KiB?
A kilobyte (KB, also written kB) is 1,000 bytes under the SI; a kibibyte (KiB) is 1,024 bytes, a binary prefix the IEC introduced in 1998. The same goes for MB and MiB, GB and GiB, and the gap grows with each step: 1 TiB is about 10% more than 1 TB.
Which systems use 1000 and which use 1024?
Storage packaging, macOS (since 10.6) and iOS use decimal units. Windows File Explorer counts in 1024s but labels them KB, MB and GB, and memory (RAM) sizes are traditionally binary too. Linux tools vary and often write KiB and MiB for binary units.
How do Mbps and MB/s relate?
A byte is 8 bits, so Mbps (megabits per second) ÷ 8 = MB/s. A 100 Mbps connection tops out at about 12.5 MB/s, a little less in practice because of protocol overhead.
Does it handle very large numbers?
Yes. Conversions use exact integers and fractions (BigInt), with no 2⁵³ floating-point limit: 16 EiB is shown exactly as 18,446,744,073,709,551,616 bytes.
Is my data uploaded?
No. Everything is calculated in your browser, with no network connection needed.