KB to MB Converter

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

megabytes = kilobytes ÷ 1000

For the binary figure, divide by 1,024 instead. At this scale the two differ by 2.4%, which is small enough to ignore for most purposes and large enough to notice on a tight upload limit.

Web performance is where kilobytes still matter. Page weight is budgeted in KB because the difference between a 200 KB page and a 2,000 KB one is the difference between loading instantly and losing the visitor:

• A well-optimised web page: 500–1,500 KB total (0.5–1.5 MB)
• A compressed JPEG for the web: 100–300 KB
• A modern WebP or AVIF of the same image: 40–120 KB
• A web font: 20–100 KB per weight
• This page's HTML, before images: usually under 100 KB

Image compression is the single biggest lever. A photo straight from a phone is 3,000–8,000 KB (3–8 MB). Resizing it to the dimensions it is actually displayed at and saving as WebP typically lands under 150 KB — a 95% reduction with no visible difference on screen.

Documents:

• A plain text file: 1–50 KB
• A Word document with no images: 20–100 KB
• A PDF with images: 500–5,000 KB

Google's Core Web Vitals measure Largest Contentful Paint, which is usually an image. Getting the largest image under about 200 KB is often the difference between passing and failing the threshold — and on a site funded by ads, a failing LCP costs both rankings and revenue.