Data size converter
Bytes, kB, MB, GB, KiB, MiB, GiB and bits, with 1000 and 1024 kept apart.
Options
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Raw value:
In every unit
| Unit | Value |
|---|---|
| Bit (bit) | – |
| Byte (B) | – |
| Kilobyte (kB, 1000 B) | – |
| Megabyte (MB, 1000² B) | – |
| Gigabyte (GB, 1000³ B) | – |
| Terabyte (TB, 1000⁴ B) | – |
| Kibibyte (KiB, 1024 B) | – |
| Mebibyte (MiB, 1024² B) | – |
| Gibibyte (GiB, 1024³ B) | – |
| Tebibyte (TiB, 1024⁴ B) | – |
| Kilobit (kbit, 1000 bit) | – |
| Megabit (Mbit, 1000² bit) | – |
| Gigabit (Gbit, 1000³ bit) | – |
kB, MB, GB and TB are decimal (1 kB = 1000 B), as on drive labels and mobile plans. KiB, MiB, GiB and TiB are binary (1 KiB = 1024 B), as Windows shows file sizes. Bits are for connection speeds; 8 bits make a byte.
A month is the average Gregorian month of 30.436875 days and a year is 365.2425 days; calendar months and years vary.
US units follow the US customary system (1 gal = 3.785 L, 1 cup = 236.6 mL); UK units follow the imperial system (1 gal = 4.546 L).
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Kilometers per hour, miles per hour, knots, m/s and ft/s, converted as you type. -
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From nanoseconds to years, converted as you type, with the average month and year stated.
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Data sizes are confusing because two systems share the same words: a 1 TB drive holds 1 000 000 000 000 bytes and Windows reports it as 931 GB, a 4.7 GB DVD is 4.38 GiB, a mobile plan of 20 GB counts in decimal gigabytes, and a 100 Mbit/s connection moves 12.5 MB per second. This page lists both: kB, MB, GB and TB are decimal (powers of 1000), KiB, MiB, GiB and TiB are binary (powers of 1024), and every unit name says which it is. Type the size, pick the units and read the result as you type, with all thirteen units in the table. Nothing is uploaded.
How to use
- Type the size, for example 4.7.
- Pick the unit you have and the unit you want; the labels say 1000 or 1024 next to each.
- Swap them to convert the other way.
- Read bits, kibibytes or terabytes in the table.
What it handles
- Thirteen units: bit, byte, kB, MB, GB, TB (decimal), KiB, MiB, GiB, TiB (binary), and kbit, Mbit, Gbit for connection speeds.
- Every unit label states its definition, 1000 B or 1024 B, so a plan, a drive label and a file manager can be compared.
- Bits and bytes are in the same table, so 100 Mbit/s converts to 12.5 MB/s by typing 100 and picking megabits to megabytes.
- Large results stay readable: 1 TB in bytes shows as 1 000 000 000 000, and only from 10¹⁵ does the page switch to scientific notation.
FAQ
Why does my 1 TB drive show 931 GB?
The drive holds 1 000 000 000 000 bytes, as the label says. Windows divides by 1024 three times and calls the result GB, which is really GiB: 1 TB is 931.32 GiB. macOS and most Linux file managers divide by 1000 and show 1 TB. Nothing is missing; the two systems just use the same letters for different sizes.
What is the difference between MB and MiB?
1 MB is 1 000 000 bytes and 1 MiB is 1 048 576 bytes, about 4.9% more. The gap grows with each step: GB versus GiB differs by 7.4%, TB versus TiB by 10%. Memory sizes, Windows file sizes and many downloads are really binary; drive labels, mobile plans and network speeds are decimal.
How do I convert Mbps to MB/s?
Divide by 8, because a byte is 8 bits: a 100 Mbit/s connection delivers at most 12.5 MB/s, and a 1 Gbit/s line 125 MB/s. Type the speed, choose megabits and megabytes, and the page does the division. Real downloads are a little slower because of protocol overhead, so a 1 GB file on 100 Mbit/s takes about 90 seconds rather than 80.
How many photos or songs fit in a gigabyte?
A gigabyte is 1000 MB. A phone photo is typically 3 to 5 MB, so about 200 to 300 photos; a 4-minute song at 320 kbit/s is about 10 MB, so around 100 songs; a minute of 4K video at 50 Mbit/s is 375 MB, so under three minutes. Type the file size and the capacity here to see the exact ratio.
Updated