Enter a size, choose the unit you have and the unit you want, and read the result instantly — plus the same size in every other unit at once. It keeps decimal units (kB, MB, GB, based on 1000) separate from binary units (KiB, MiB, GiB, based on 1024), which is exactly the mix-up behind "my 1 TB drive only shows 931 GB". Everything runs in your browser.
In all units
- Bit (bit)8,000,000,000 bit
- Byte (B)1,000,000,000 B
- Kilobyte (kB) — 10001,000,000 kB
- Megabyte (MB) — 10001,000 MB
- Gigabyte (GB) — 10001 GB
- Terabyte (TB) — 10000.001 TB
- Petabyte (PB) — 10000.000001 PB
- Kibibyte (KiB) — 1024976,562.5 KiB
- Mebibyte (MiB) — 1024953.674316 MiB
- Gibibyte (GiB) — 10240.931323 GiB
- Tebibyte (TiB) — 10240.000909 TiB
How it works
Every unit is defined by how many bytes it holds, and all conversions go through the byte as a common base. Decimal units use powers of 1000 (1 kB = 1,000 B, 1 MB = 1,000,000 B) as defined by SI; binary units use powers of 1024 (1 KiB = 1,024 B, 1 MiB = 1,048,576 B) as defined by the IEC. One bit is one eighth of a byte.
The two families are offered together because storage is sold in decimal while operating systems often report capacity in binary, using the same "GB" label. That is why a drive marked 1 TB (10¹² bytes) shows up as about 0.909 TiB, or "931 GB" in a file manager that means GiB. Converting between the families makes the gap explicit instead of surprising.
Practical examples
Why a 1 TB drive looks smaller
A 1 TB drive holds 1,000,000,000,000 bytes. Convert 1 TB to TiB and you get about 0.909 — which a computer displays as roughly 931 GiB, not 1000. No space is missing; the units differ.
Upload limit in MB to bytes
A form that accepts files up to 25 MB is 25,000,000 bytes (decimal). Convert MB to bytes when an API or config wants the limit as a raw byte count.
RAM in GiB vs a GB label
A "16 GB" RAM module is 16 GiB in practice — 17,179,869,184 bytes. Convert GiB to GB to see it advertised as about 17.18 GB.
Frequently asked questions
What is the difference between MB and MiB?
A megabyte (MB) is 1,000,000 bytes; a mebibyte (MiB) is 1,048,576 bytes (1024²). MiB is about 4.9% larger. The names exist precisely to remove the ambiguity that the single label "MB" used to carry.
Why does my hard drive show less space than advertised?
Manufacturers sell in decimal (1 TB = 10¹² bytes) while Windows reports in binary but labels it "GB". The bytes are all there — 1 TB is about 931 GiB. Convert TB to TiB here to see the exact figure.
How many megabytes are in a gigabyte?
In decimal, 1 GB = 1,000 MB. In binary, 1 GiB = 1,024 MiB. This tool keeps both so you get the right answer for the context — storage marketing (decimal) or an operating system (binary).
What is a bit versus a byte?
A byte is eight bits. Storage is measured in bytes, but network and connection speeds are often quoted in bits (megabits, Mb), which is why a "100 Mbps" line downloads at roughly 12.5 MB/s.
Which family should I use, decimal or binary?
Use decimal (kB, MB, GB) for storage capacity, file sizes shown by most tools, and bandwidth. Use binary (KiB, MiB, GiB) when a program, operating system or spec explicitly reports capacity in powers of 1024.
How do I convert kilobytes to megabytes?
Divide by 1,000 for decimal units: 2,500 kB is 2.5 MB. Enter the value in kilobytes and read the megabyte row — the tool handles both the decimal and binary interpretations.
Does it handle very large or very small numbers?
Yes, up to petabytes and down to single bits. Results are shown to six decimal places with trailing zeros trimmed, and large byte counts are grouped with locale separators for readability.
Does it accept the decimal comma?
Yes. You can type 1,5 or 1.5 and both mean one and a half. Grouping separators in pasted numbers are read too, so 1.024 is understood correctly.
Are the values I enter uploaded anywhere?
No. The conversion runs entirely in your browser; nothing is sent to a server and analytics never receives the numbers.
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