How many kB are in a MB?

1 MB equals 1000 kB. Multiply a MB value by 1000 to get kB.

How many kB is a 5 MB photo?

A 5 MB photo equals 5000 kB. Upload forms that set limits in kB need that number.

How many kB are in 100 MB?

100 MB equals 100000 kB. Each extra 10 MB adds 10000 kB.

Why do I see 1024 when I convert MB to KB?

Tools that count in binary units set 1 MiB equal to 1024 KiB. This converter uses decimal units, so 1 MB equals 1000 kB and about 976.56 KiB.

Megabyte (MB) to Kilobyte (kB) Converter

Enter a value to instantly convert between data storage units.

From

Precision4 dp

1 Megabyte = 1000 Kilobyte

Key Formulas

Megabyte → Gigabyte

GB = MB × 0.001

Gigabyte → Megabyte

MB = GB × 1000

Gigabyte → Terabyte

TB = GB × 0.001

Terabyte → Gigabyte

GB = TB × 1000

Formula

kB = MB × (1000000 / 1000)

Multiply megabytes by 1,000 to get kilobytes, because one megabyte is 1,000 kilobytes in decimal units. For example, 5 MB is 5,000 kB. Use this pair to compare a photo or song size in megabytes with a limit set in kilobytes, such as a form field, an email gateway, or a firmware slot on a small device. In binary units, 1 MiB is 1,024 KiB, and this page uses the decimal factor.

Source: NIST: decimal prefixes and explicit binary prefixes; 1 byte = 8 bits

Reviewed by the Convert Calc editorial team · Last reviewed: 2026-10-06 · see our methodology

Frequently Asked Questions

Real-World Examples

A 1 MB profile photo is 1000 kB on a site that sets limits in kB.

1 MB = 1000 kB

A 5 MB phone photo is 5000 kB.

5 MB = 5000 kB

A 10 MB PDF is 10000 kB when an upload form asks for kB.

10 MB = 10000 kB

A 100 MB log file holds 100000 kB of text.

100 MB = 100000 kB

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See This in Context

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