Convert data sizes between bits, bytes, KB, MB, GB, TB and the binary KiB, MiB, GiB, TiB — with the decimal-vs-binary trap explained.
What Is a Data Storage Converter?
A data storage converter translates digital sizes — and explains why your “1 TB” drive shows 931 GB. Drive makers use decimal: 1 GB = 1,000,000,000 bytes. Operating systems traditionally use binary: 1 GiB = 1,073,741,824 bytes (2^30). So 1 TB decimal = 931.32 GiB binary — the “missing” space was never missing, just measured differently. The IEC binary prefixes (KiB, MiB, GiB, TiB) exist precisely to end this confusion.
How to Use
- Enter the value.
- Pick the “from” unit — note GB vs GiB.
- Pick the “to” unit.
- Click “Convert Data”.
Formula
Convert to bytes first (value × from-factor), then divide by the to-factor.
Worked Example
1 GiB → MiB: 1,073,741,824 ÷ 1,048,576 = 1,024 MiB. And 1 GB → MB: 1,000,000,000 ÷ 1,000,000 = 1,000 MB.
How It Works, In Plain Words
Every unit in the two lists is stored as a factor in bytes, and bytes are the bridge the Formula line describes. The bit is 0.125 of a byte, because there are 8 bits in a byte, and the byte itself is 1. The decimal family then climbs in thousands: KB is 1,000 bytes, MB is 1,000,000, GB is 1,000,000,000 and TB is 1,000,000,000,000. The binary family climbs in 1,024s instead: KiB is 1,024 bytes, MiB is 1,048,576, GiB is 1,073,741,824 and TiB is 1,099,511,627,776. To convert, the tool multiplies your value by the from-factor to land in bytes, then divides by the to-factor. The worked example runs exactly that path: 1 GiB becomes 1,073,741,824 bytes, and dividing by the MiB factor of 1,048,576 gives 1,024 MiB. The decimal example stays inside its own family: 1,000,000,000 ÷ 1,000,000 = 1,000 MB. Crossing families costs nothing extra, because both sides pass through the same bytes — which is how 1 TB turns into 931.32 GiB without any special case.
One display detail is worth knowing: the result is printed with up to four decimal places. Converting a small size into a big unit produces a long decimal rather than a flat zero, so the answer stays readable at both ends of the scale.
Real-World Uses
A buyer plugging in a new drive labelled “1 TB” watches the computer report 931 GB and wants to know whether space has gone missing. Converting 1 TB into GiB gives 931.32 — the What Is section’s own figure — so the drive is full size and only the measuring stick changed. A home user whose downloads never seem to match the advertised broadband speed converts through the bit unit: the mistakes list works the same sum, 100 Mbps = 12.5 MB/s, because the speed is sold in bits while the download manager reports bytes. A photographer checking whether a card has room for a shoot converts the folder size from MB into GB — decimal, matching how the card is labelled — instead of comparing two numbers measured in different families and hoping for the best.
Benefits
- Ten units with the decimal/binary split made explicit
- Explains the “missing drive space” mystery
- Both directions in one tool
- Bits included for network speeds
Features of Our Tool
- Instant results in your browser
- No sign-up, no download, 100% free
- Works on mobile, tablet and desktop
- Clear step-by-step explanation below the tool
- Private — your entries never leave your device
Common Mistakes
- Comparing GB and GiB as if equal — 7.4% apart at the giga scale
- Confusing bits and bytes on internet speeds (100 Mbps = 12.5 MB/s)
- Expecting the drive label to match the OS — they use different definitions
Common Mistakes to Avoid
The list above names the three traps, and they share one root: two numbers that look comparable but are measured differently. Comparing GB and GiB as if equal is the classic — they are about 7.4% apart at the giga scale, and the gap only widens higher up, which is why 1 TB shows as 931.32 GiB rather than anything near 1,000. Confusing bits and bytes flatters every internet connection by a factor of eight: 100 Mbps is 12.5 MB/s, not 100. Expecting the drive label to match the operating system ignores that the maker counts decimal and the system counts binary. The guard for all three is the same habit — read the unit letters before the number, treat the little “i” in KiB, MiB and GiB as the warning sign it is, and convert both sides into one unit before you compare them.
FAQ
Why does my 1 TB drive show 931 GB?
The maker counts 1 TB = 1,000,000,000,000 bytes; your OS counts in GiB (1,073,741,824 bytes) — 1 TB decimal = 931.32 GiB.
How many MiB in a GiB?
1,024 MiB.
How many MB in a GB?
1,000 MB (decimal).
What is the difference between GB and GiB?
GB = 10^9 bytes (decimal); GiB = 2^30 bytes (binary) — about 7.4% apart.
How many bits in a byte?
8 bits.
Why does the gap between the two families grow at bigger units?
Because each step compounds. The decimal family multiplies by 1,000 while the binary family multiplies by 1,024, so every step up adds another slice of difference: GB and GiB end up about 7.4% apart, and by the tera scale 1 TB reads as 931.32 GiB. The same mix-up that barely matters for a small file moves real space at drive sizes.
Can I convert an internet speed with this tool?
Yes, through the bit unit. Speeds are sold in bits per second while apps report bytes, and there are 8 bits in a byte — the mistakes list works the example: 100 Mbps = 12.5 MB/s. Enter the speed as bits and convert to MB to see the per-second figure your download manager shows, and expect it to look roughly eight times smaller than the headline speed.