Magerøya has an area of 436.6 square kilometres (168.6 sq mi) and the highest elevation on the island is the 417-metre (1,368 ft) mountain Gråkallfjellet.

The island features a bleak, barren, tundra-covered landscape devoid of any trees (except for a few small pockets of mountain birch), with steep cliffs along the coast, and dramatic mountainscapes in the interior.

On southern Magerøya, archaeologists have found evidence of settlements dating back 10,000 years.

It is 6.87 kilometres (4 mi 473 yd) long and reaches a depth of 212 metres (696 ft) below sea level.

Norway's Hurtigruten ferry service stops at the town of Honningsvåg on Magerøya since the waters around the island remain ice-free all year round due to the warm North Atlantic drift.