MB to KB Converter

Convert megabytes to kilobytes instantly, with a reference table for upload limits and image budgets.

Megabytes

Kilobytes

1 MB = 1,000 KB

Multiply megabytes by 1,000 to get kilobytes.

The link carries the values you entered, so whoever opens it sees the same result. Nothing is stored on our side — the numbers travel in the link itself.

Megabytes to kilobytes reference table

The conversions people look up most often, rounded to 2 decimal places.

Common megabytes to kilobytes conversions
Megabyte (MB)	Kilobyte (KB)
0.1 MB	100 KB
0.25 MB	250 KB
0.5 MB	500 KB
1 MB	1,000 KB
2 MB	2,000 KB
5 MB	5,000 KB
10 MB	10,000 KB
20 MB	20,000 KB
25 MB	25,000 KB
50 MB	50,000 KB
100 MB	100,000 KB
500 MB	500,000 KB
1,000 MB	1,000,000 KB

The megabytes people look up most

0.25 MB = 250 KB: About a compressed web page with its images, which is the budget worth aiming at.
1 MB = 1,000 KB: A high-quality phone photograph is several of these.
5 MB = 5,000 KB: A per-file attachment limit on many older corporate mail systems.
10 MB = 10,000 KB: Roughly a minute of MP3 audio at a respectable bitrate.
25 MB = 25,000 KB: The usual Gmail attachment ceiling, which is why bigger files arrive as a Drive link.
100 MB = 100,000 KB: A short phone video, and a common free-tier upload cap.

How the mb to kb calculation works

Using the decimal definition, 1 MB = 1,000 KB:

kilobytes = megabytes × 1000

Multiply by 1,024 instead if you need the binary figure — 1 MiB is 1,024 KiB.

This conversion usually gets done in one direction for one reason: a form has a size limit in KB and your file is in MB.

0.5 MB → 500 KB
1 MB → 1,000 KB
2 MB → 2,000 KB
5 MB → 5,000 KB

Common limits, converted:

Limit	In KB
Passport photo upload, often 240 KB	0.24 MB
Government forms, often 2 MB	2,000 KB
Gmail attachment, 25 MB	25,000 KB
Most job application portals, 5 MB	5,000 KB

How to actually get under a limit. For a photo, resolution is the lever, not the quality slider: halving both dimensions cuts the pixel count to a quarter and the file size by roughly as much. Dropping JPEG quality from 100 to 80 typically halves the size again with no visible loss — quality 100 spends most of its bytes on detail no eye will see.

For a PDF, the size is almost always embedded images rather than text. Exporting at 150 dpi instead of 300 dpi usually gets a document under a 2 MB limit, and stays sharp on screen. 300 dpi only matters if it will be printed.

Screenshots are deceptively large. A full-screen PNG can be 3–5 MB; saving the same image as JPEG usually lands under 500 KB.

Frequently asked questions

How large is a typical photograph?

A phone photo is usually 2,000 to 5,000 KB depending on resolution and compression, while a camera RAW file is roughly ten times that. Screenshots are often under 1,000 KB because flat interface colours compress extremely well. The content matters far more than the megapixel count.

Why does an email bounce when the file is under the limit?

Because the limit applies to the encoded message rather than the file. Email transports binary data as base64, which inflates it by about a third, so a 20 MB attachment travels as roughly 27 MB of message. A service advertising a 25 MB ceiling will often refuse a 20 MB file for exactly this reason.

Is a kilobyte 1,000 bytes or 1,024?

Both are in circulation. The SI kilobyte is 1,000 bytes; the kibibyte is 1,024. At this scale the difference is small enough to ignore for a single file, but it compounds at every step, which is how a modest discrepancy in kilobytes becomes a visible one in terabytes.

MB to KB Converter