Convert Megabyte to Kilobyte (MB → KB)

Converting megabytes to kilobytes is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

1. 1
   Take your value in megabytes

   Start with the number of megabytes (MB) you want to convert.
2. 2
   Multiply by 1,000

   The conversion factor from MB to KB is 1,000. Multiply your value by this number.
3. 3
   Read the result in kilobytes

   The result is your value in kilobytes (KB).

Multiply the value in megabytes by 1,000. For the reverse direction, multiply by 0.001.

• ✓SI: 1 MB = 1000 KB = 1,000,000 B.
• ✓Binary MiB = 1,048,576 B — 4.86% larger.
• ✓HD drives, networks, SSDs: SI MB.

• ✗Mixing MB and MiB without noting the difference (~5%).
• ✗Confusing MB (storage) with Mb (megabit, 1/8).
• ✗Assuming 1 GB = 1000 MB always — correct in SI; binary it's 1024.

What is the Megabyte?

The megabyte (MB) equals 1,000 kilobytes (1,000,000 bytes decimal, or 1,048,576 bytes binary as MiB). It is the everyday unit for image files, MP3 songs, and small documents on personal computers. A high-quality JPEG photograph is 2–10 MB, an MP3 song is 3–10 MB, a Microsoft Word document might be 0.05–5 MB, and a typical e-book is under 5 MB. Older USB flash drives and CDs hold hundreds of MB (a CD is 700 MB). Mobile data plans were originally measured in MB before gigabyte plans became standard. The megabyte relates to the kilobyte (1,000 KB = 1 MB), the gigabyte (1,000 MB = 1 GB), and the megabit (1 MB = 8 Mbit). Internet connection speeds are usually rated in Mbps (megabits per second), distinct from MBps (megabytes per second): 100 Mbps = 12.5 MBps.

• Photo and image file sizes
• MP3 and audio files
• Small video clips

What is the Kilobyte?

The kilobyte (KB) equals 1,000 bytes (decimal) or sometimes 1,024 bytes (binary, properly KiB). In modern strict usage, KB = 10³ bytes and KiB = 2¹⁰ bytes, but historical software and operating systems often interchanged them. The kilobyte was the standard file-size unit in early computing: a typical floppy disk held 360–1,440 KB, early word-processor documents were a few KB. Today, the kilobyte is rarely the primary user-facing unit (megabytes and gigabytes dominate), but it remains relevant for small files, source-code text, and embedded systems memory. The original Apple Macintosh (1984) shipped with 128 KB of RAM; the original IBM PC had 16–640 KB. The kilobyte relates to the byte (1,000 bytes = 1 KB decimal, 1,024 bytes = 1 KiB binary), the megabyte (1,000 KB = 1 MB), and the kilobit (1 KB = 8 kbit).

• Small file sizes (icons, short documents)
• Network packet sizes
• Early-computing memory specifications