Megabytes to Kilobytes Converter
Convert megabytes to kilobytes and understand the difference between decimal (1000) and binary (1024) file-size units.
Result
Kilobytes (KB)
1 Megabytes (MB) = 1024 Kilobytes (KB)
How to convert Megabytes (MB) to Kilobytes (KB)?
Note: “KB” can be used in two different ways depending on the context.
- Decimal (SI): 1 MB = 1000 KB
- Binary (IEC): 1 MiB = 1024 KiB (often shown as “1024 KB per MB” in some tools)
This converter uses a 1024-based factor as specified in the page settings.
Formula (1024-based): Kilobytes (KB) = Megabytes (MB) × 1024
Step-by-Step Calculation (1024-based)
- Take the number of Megabytes (MB) you want to convert (e.g., 10).
- Multiply that value by 1024.
- The result is the value in Kilobytes (KB). (Example: 10 × 1024 = 10240 KB).
KB vs KiB: why the numbers don’t always match
Strictly speaking, kB (kilobyte) is decimal and equals 1000 bytes, while KiB (kibibyte) is binary and equals 1024 bytes.
Many apps still display “KB” even when they’re using 1024-based calculations, which can create confusion.
Real-world use cases (images, email attachments, upload limits)
- Image optimization: If you compress a photo from 2.4 MB to 900 KB, MB↔KB helps you compare file sizes quickly.
- Email attachments: Some services limit attachments in KB/MB—this conversion helps you stay under the limit.
- Website performance: Reducing a page by 300 KB can meaningfully improve load times on mobile connections.
How to use this converter?
Common MB to KB Conversions (1024-based)
Quick reference guide for typical file sizes using a 1024-based factor.
Note: 1000 vs 1024
MB to KB Conversion Table (1024-based)
| Megabytes (MB) Input | Kilobytes (KB) Result |
|---|---|
| 0.25 MB | 256 KB |
| 0.5 MB | 512 KB |
| 1 MB | 1024 KB |
| 1.5 MB | 1536 KB |
| 2 MB | 2048 KB |
| 5 MB | 5120 KB |
| 10 MB | 10240 KB |
| 25 MB | 25600 KB |
| 50 MB | 51200 KB |
| 100 MB | 102400 KB |
Frequently Asked Questions
How do I convert MB to KB?
If you mean decimal units, multiply MB by 1000 to get KB. If you’re using a 1024-based calculation, multiply by 1024 (more precisely: MiB→KiB).
How many KB is 1 MB?
In strict decimal terms, 1 MB = 1000 KB. Using a 1024-based calculation, 1 × 1024 = 1024 KB (more precisely: 1 MiB = 1024 KiB).
How many KB is 10 MB?
Using a 1024-based calculation: 10 × 1024 = 10240 KB. In decimal labeling: 10 MB = 10000 KB.
Why do some tools use 1000 instead of 1024?
1000 is the decimal (SI) standard. 1024 is the binary (IEC) standard (KiB/MiB/GiB). Different apps and platforms choose different conventions.
Is this conversion exact?
It’s exact for the chosen factor. 1024-based conversions are exact in the binary system (MiB→KiB). Decimal labeling commonly uses 1000 (MB→KB).