Gigabytes (GB) to Kilobytes (KB) Converter
Enter your Gigabytes (GB) value to convert to Kilobytes (KB). 1 GB = 1,000,000 KB, calculated across both decimal (SI) and binary (IEC) standards.
Convert Gigabytes to Kilobytes
Do you want to convert kilobytes to gigabytes?
How to Convert Gigabytes to Kilobytes
To convert gigabytes to kilobytes, multiply by 1,000,000 (using SI decimal). Both units measure storage capacity—the difference is scale. See also: Kilobytes to Gigabytes conversion.
GB: A gigabyte is 1,000 megabytes or 1,000,000,000 bytes using the SI decimal standard. This is what hard drive manufacturers typically use. Try the GB to Yobibits converter.
KB: A kilobyte is 1,000 bytes using the SI decimal standard. Commonly used for small file sizes. Check out our Kibibits to KB calculator.
1 GB = 1,000,000 KB (using SI decimal standard) — which means there are 1,000,000kilobytes in every gigabyte.
GB to KB Conversion Formula
// Convert GB to KB
KB = GB × 1,000,000
// Reverse: Convert KB to GB
GB = KB × 0.000001
GB to KB Conversion Examples
100 GB = 100,000,000 KB
256 GB = 256,000,000 KB
500 GB = 500,000,000 KB
1,000 GB = 1,000,000,000 KB
2,048 GB = 2,048,000,000 KB
Binary Standard (Base 1024)
Using binary calculation: 1 GB = 1,048,576 KB
100 GB = 104,857,600 KB
1,000 GB = 1,048,576,000 KB
1,024 GB = 1,073,741,824 KB
What Is a Gigabyte?
A gigabyte is 1,000 megabytes or 1,000,000,000 bytes using the SI decimal standard. This is what hard drive manufacturers typically use. Use our convert MB to Exbibits.
The gigabyte is a SI decimal unit of digital information storage. It uses base 1,000 following the SI (International System of Units) standard. Check out our Megabytes Per Second to KiB/s.
Common uses: Movies, video games, smartphone storage, USB drives, cloud storage plans Related: how many Zib in Gigabytes.
1 GB = 8 × 10⁹ bits = 1 × 10⁹ bytes.
The gigabyte can be abbreviated as GB; for example, 1 gigabyte can be written as 1 GB.
What Is a Kilobyte?
A kilobyte is 1,000 bytes using the SI decimal standard. Commonly used for small file sizes. Use our how many Kilobytes in a b.
The kilobyte is a SI decimal unit of digital information storage. It uses base 1,000 following the SI (International System of Units) standard. Related: calculate MB to Kb.
Common uses: Text documents, small images, email attachments, configuration files Try the Yibps to Kbps conversion rate.
1 KB = 8,000 bits = 1,000 bytes.
The kilobyte can be abbreviated as KB; for example, 1 kilobyte can be written as 1 KB.
Gigabyte to Kilobyte Conversion Table
The table below shows various gigabyte measurements converted to kilobytes.
| Gigabytes | Kilobytes | Kilobytes (Binary) |
|---|---|---|
| 1 GB | 1,000,000 KB | 1,048,576 KB |
| 2 GB | 2,000,000 KB | 2,097,152 KB |
| 5 GB | 5,000,000 KB | 5,242,880 KB |
| 10 GB | 10,000,000 KB | 10,485,760 KB |
| 25 GB | 25,000,000 KB | 26,214,400 KB |
| 50 GB | 50,000,000 KB | 52,428,800 KB |
| 100 GB | 100,000,000 KB | 104,857,600 KB |
| 128 GB | 128,000,000 KB | 134,217,728 KB |
| 250 GB | 250,000,000 KB | 262,144,000 KB |
| 256 GB | 256,000,000 KB | 268,435,456 KB |
| 500 GB | 500,000,000 KB | 524,288,000 KB |
| 512 GB | 512,000,000 KB | 536,870,912 KB |
| 1,000 GB | 1,000,000,000 KB | 1,048,576,000 KB |
| 1,024 GB | 1,024,000,000 KB | 1,073,741,824 KB |
SI Decimal vs Binary: Why Two Different Standards?
When converting gigabytes to kilobytes, different tools may give slightly different results. This is because there are two competing standards for measuring digital storage:
| Standard | Base | 1 KB equals | Used By |
|---|---|---|---|
| SI Decimal | 1000 | 1,000 bytes | Hard drive manufacturers, macOS, network speeds |
| Binary (IEC) | 1024 | 1,024 bytes | Windows, Linux (partially), RAM specifications |
Why Does My Hard Drive Show Less Space Than Advertised?
This difference in standards explains the common "missing hard drive space" confusion.
Example: A "500 GB" Hard Drive
- Contains exactly: 500,000,000,000 bytes
- macOS (SI Decimal): Displays 500 GB (divides by 1,000³)
- Windows (Binary): Displays 465 GB (divides by 1,024³)
The Verdict: Same bytes, same drive—just different math. No space is actually missing.
Note: Our calculator defaults to SI decimal (base 1000) to match the box label. To match Windows, toggle the standard at the top of the calculator.
💡 Storage Engineer Tip
Manufacturers label drives using SI decimal (base 1000). Windows divides by 1024 instead—that's why a "1 TB" drive shows as 931 GB. Same bytes, different math.
— Subash Geetha Krishnan, 15+ years in enterprise storage
When to Convert GB to KB
Common scenario: Planning storage allocation, comparing specifications, or converting between gigabyte and kilobyte for capacity planning. Check out our converting Gigabytes to Tebibits.
Other situations include storage planning for calculating how much data fits in a given capacity, file management for understanding sizes across different scales, cost estimation for budgeting cloud storage, and backup planning for determining media requirements. Check out our Zb to KB calculator.