The biggest, the Island of Elba, (third largest island in Italy), measures 223,5 square kilometres, and has 147 km of coastline.

The distance from east to west is about 27,3 kilometres, while the distance from north to south is about 18,4 km. After that comes the island of Giglio, that measures about 21,2 square kilometres. It has a longish shape, about 8,6 km, and measures 4,3 km at its narrowest part. Capraia measures about 19,3 square kilometres, so it is the third largest island in the Archipelago. At its longest point it measures 7,9 km, and a little less than 4 km at its widest. Montecristo measures about 10,4 square kilometres and has 16 km of coastline; it's a little less than 4,3 km long and under 4 km wide.

The Island of Pianosa measures 10,25 square kilometres, and has 26 km of coastline. It is 5,78 km from north to south, and 4,7 km from east to west. The Island of Giannutri measures 2,6 square kilometres, and from north to south is about 2,7 km, while from east to west it measures about 2 km. The smallest island in the Archipelago is Gorgona. It measures only 2,23 square kilometres, and has a coastline of only 5 kilometres. From north to south it measures about 2,2 km, while from east to west t is about 1,57 km.