Question 1

What is the difference between GB and GiB?

Accepted Answer

1 GB (gigabyte, SI decimal) equals 1,000,000,000 bytes (10⁹), whereas 1 GiB (gibibyte, IEC binary) equals 1,073,741,824 bytes (2³⁰). A 2 GiB file is roughly 2.147 GB in decimal bytes.

Question 2

Why does Windows show a smaller number than macOS for the same file?

Accepted Answer

macOS Finder and storage manufacturers report decimal SI gigabytes (dividing by 1,000³), whereas Windows Explorer historically divides by 1,024³ (binary GiB) while labelling it 'GB'.

Question 3

Does Attach & Send measure transfer limits in GB or GiB?

Accepted Answer

Attach & Send states limits in decimal SI gigabytes (for example, the 2GB Guest transfer limit is exactly 2,000,000,000 bytes) and lets you toggle between SI (GB/TB) and IEC (GiB/TiB) on our Pricing page.

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