How many bytes are in 1 GB?

In the SI decimal standard used by storage manufacturers and most consumer devices, 1 GB = 1,000,000,000 bytes (10^9). This differs from the binary standard.

What is the difference between GB and GiB?

GB (gigabyte) uses base-10: 1 GB = 1,000,000,000 bytes. GiB (gibibyte) uses base-2: 1 GiB = 1,073,741,824 bytes. Windows commonly reports binary-sized values with decimal labels; current macOS reports storage using decimal units.

How many bytes are in 1 GiB?

1 GiB = 2^30 = 1,073,741,824 bytes. This is the binary standard defined by IEC 80000-13.

Why does my 1 TB drive show less space in some operating systems?

Drive makers measure in SI TB (10^12 bytes). Systems that display the same bytes in binary GiB show about 931 GiB; current macOS uses decimal storage units, though formatting and system files still reduce available capacity.

Gigabytes to Bytes Converter

Convert gigabytes to bytes using SI decimal (1 GB = 1,000,000,000 B) or binary IEC (1 GiB = 1,073,741,824 B).

Gigabytes to Bytes

Gigabytes

Standard

SI decimal (GB = 10⁹ B) IEC binary (GiB = 2³⁰ B)

Enter a value to see the byte conversion

Quick Reference

Gigabytes	Bytes (SI · GB)	Bytes (IEC · GiB)

Copied!

Summary

Enter a value in gigabytes and instantly see the equivalent in bytes. Supports both SI decimal (GB) and IEC binary (GiB) standards so you get the right number for disk capacity, RAM, or network bandwidth calculations.

How it works

Enter a gigabyte value in the input field.
Select SI decimal (GB) or IEC binary (GiB) standard.
The byte result appears instantly below.
Click Copy to copy the raw byte number to your clipboard.

Use cases

Calculate exact byte count for disk or SSD capacity comparisons.
Determine memory requirements for software or operating system specifications.
Convert cloud storage quotas from gigabytes to bytes for API calls.
Verify network bandwidth figures when working with throughput calculations.

Frequently Asked Questions

Last updated: 2026-06-19 · Reviewed by Nham Vu