Brunei is about 257 times smaller than Alaska.

Alaska is approximately 1,481,348 sq km, while Brunei is approximately 5,765 sq km, making Brunei 0.39% the size of Alaska. Meanwhile, the population of Alaska is ~710,231 people (232,177 fewer people live in Brunei).
Tip: This to-scale comparison of Alaska vs. Brunei uses the Mercator projection, which distorts the size of regions near the poles.