how wide is a king size bed

A standard king size bed is typically 76 inches (193 cm) wide and 80 inches (203 cm) long in the U.S. and Canada.

Quick Scoop

• Standard king width: 76 inches (about 6 feet 4 inches).

• Standard king length: 80 inches.

• It’s the widest common mattress size (wider than queen and California king).

Regional twists

• In some countries (like the UK and parts of Europe), “king” can be a bit narrower, often around 150–165 cm wide (about 59–65 inches).

• A California king is narrower but longer : about 72 inches wide by 84 inches long.

Easy way to picture it

If you place two twin XL mattresses side by side, you basically get the width and length of a standard king (76 x 80 inches total), which is why split kings are popular adjustable setups.

TL;DR: When people ask “how wide is a king size bed,” they almost always mean 76 inches (193 cm) wide.