Storage units
MB vs GB vs GiB: What Is the Difference?
Compare MB, GB, MiB and GiB, understand decimal and binary storage units, and explain why a drive can appear smaller after formatting.
A decimal gigabyte is 1,000,000,000 bytes. A binary gibibyte is 1,073,741,824 bytes, or 1,024³. MB and MiB follow the same distinction.
The key idea
Drive manufacturers commonly use decimal GB and TB, while operating systems may display a binary-sized value but label it GB. Formatting and reserved system space reduce usable capacity too.
Decimal and binary storage units
| Unit | Bytes | System |
|---|---|---|
| 1 MB | 1,000,000 | Decimal |
| 1 MiB | 1,048,576 | Binary |
| 1 GB | 1,000,000,000 | Decimal |
| 1 GiB | 1,073,741,824 | Binary |
To convert GB to GiB, multiply by 1,000,000,000 and divide by 1,073,741,824. A 500 GB drive therefore contains about 465.66 GiB before formatting and system partitions.
Why a new drive appears smaller
A manufacturer may advertise 1 TB as one trillion bytes. Software displaying the same byte count in binary units shows about 931 GiB, sometimes while still labeling it “GB.” Formatting, recovery partitions and the operating system reduce available capacity further. The difference does not automatically mean storage is missing.
Storage size versus network speed
File sizes use bytes; internet plans commonly use bits per second. Eight bits equal one byte, so 100 megabits per second has a theoretical maximum near 12.5 megabytes per second before overhead. Use the file transfer time calculator instead of treating Mbps and MB/s as identical.
Plan storage using one unit
Convert every figure to the same unit before adding it, then include backups, exports, cache and growth. A video editor needs room for source clips and working files, not only the final video. Use the storage needed for files calculator for repeated files and the GB to GiB converter when specifications and software use different standards.
A practical workflow
Use the GB/GiB converter when a specification and a device display use different conventions. Write the unit beside every result so a reader knows which definition was used.
Checks and limitations
For backups or video projects, estimate the original files and add room for exports and growth. A storage calculator can help, but confirm the actual device specification before buying.
Check the result in the working tool
Open the GB and GiB converter with the same values used in the example. Read the labels and units beside the result, then keep the source information until the output has been checked for its intended use.
Quick answers
Frequently asked questions
Is 1 GB equal to 1,024 MB?
In decimal units, 1 GB equals 1,000 MB; binary units use 1,024 MiB per GiB.
Is GiB larger than GB?
One GiB contains more bytes than one GB. However, the same fixed byte count produces a smaller numeric value when expressed in GiB.
Why does Windows sometimes say GB for a binary value?
Some interfaces calculate using powers of 1024 while displaying a decimal-style label. Compare the byte count when the exact convention matters.
How many GiB are in 1 TB?
One decimal terabyte is approximately 931.32 GiB. The usable amount shown by a device may be lower after formatting, partitions and system files.
Use the tool