Data Storage Converter (MB, GB, GiB, TB)
Megabytes to gigabytes, GB to GiB — with the 1000 vs 1024 difference made explicit instead of fudged.
Fast, easy and free — your answer appears as you type, and whatever you enter stays on your device.
Convert between bytes, kilobytes, megabytes, gigabytes and terabytes — and their binary cousins KiB, MiB, GiB and TiB. The 1000-versus-1024 distinction is made explicit, because it is the whole reason a 1 TB drive shows up as 931 GB.
How to use it
- Pick your unitsDecimal units (KB, MB, GB) use powers of 1000. Binary units (KiB, MiB, GiB) use powers of 1024. Both families are listed.
- Type the amountThe answer appears as you type; Swap reverses the direction.
- Check the factorThe exact multiplier is shown beneath the result.
Two counting systems, one label
Data sizes are the only everyday measurement where the same label is used for two different quantities on purpose. Decimal units follow SI: kilo is 1000, mega is a million. Binary units follow powers of two: 1024, 1,048,576. Hardware makers use decimal, much software historically used binary, and both print "GB". Every mysterious size discrepancy you have ever seen — the shrinking drive, the download that is "bigger" than the file — is this one disagreement wearing a costume.
The honest fix, adopted in 1998, was to give binary its own names: kibibyte, mebibyte, gibibyte. This converter lists both families so the difference is visible instead of silently absorbed: type 1 GB and the GiB answer is 0.9313, not 1.
Bits, bytes and download times
The other daily confusion is bits versus bytes. Connection speeds are sold in megabits per second; files are measured in megabytes. Eight bits to the byte means a 500 Mbps line moves at most 62.5 MB/s — so a 5 GB game takes at least 80 seconds on paper, and longer in practice. Converting a speed to bytes before estimating a download saves the routine eightfold disappointment.
When precision matters
For most sizing questions the 2.4% at KB scale is noise. It stops being noise in three places: buying storage (7–10% at GB and TB scale is real money), quota limits (a backup that is 4.9 GiB does not fit a "5 GB" limit that turns out decimal), and anything programmatic, where mixing the two systems produces off-by-4.9% bugs that look like corruption. In all three cases the fix is the same: convert to plain bytes and compare those.
Whatever you enter stays on your device, and the tool keeps working offline once loaded.
Questions people ask
Why does my 1 TB drive show only 931 GB?
Nothing is missing. The drive maker counts in decimal — 1 TB = 1,000,000,000,000 bytes, which is correct SI usage. Windows divides that same number by 1024 three times and displays 931, labelling it GB when the unit it computed is really GiB. Same bytes, two counting systems, and this converter shows both: 1 TB = 0.909 TiB.
What is the difference between MB and MiB?
A megabyte (MB) is 1,000,000 bytes. A mebibyte (MiB) is 1,048,576 bytes — 1024 squared. The gap is about 4.9% at this scale and grows with each step: about 7.4% at GB/GiB and 10% at TB/TiB. The 'bi' units were standardised in 1998 precisely to end the ambiguity, though adoption remains patchy.
Which one does my phone or ISP mean?
Storage makers and network providers use decimal (a 100 Mbps line is 100,000,000 bits per second). Operating systems vary: macOS and Linux tools mostly show decimal these days, Windows still shows binary quantities with decimal labels. When a figure matters, convert to plain bytes — that is the one unit nobody redefines.
How many photos or songs is a gigabyte?
Rough working figures: a phone photo is 3–5 MB, so a gigabyte holds 200–300 photos. A streamed song is about 3–4 MB, an hour of HD video 1.5–3 GB. These vary with quality settings, but they are the right order of magnitude for sizing storage.
Why is a bit an eighth of a byte?
A byte is 8 bits by universal convention. It matters because network speeds are quoted in bits (megabits per second) while file sizes are quoted in bytes — a '100 Mbps' connection downloads at most 12.5 MB per second. Dividing by 8 turns advertised speed into real-world file time.
Are these conversions exact?
Completely — both families are exact integer definitions. The only rounding is in the displayed answer.