Wormer is a town in the Dutch province of North Holland. It is a part of the municipality of Wormerland, and lies about 13 km northwest of Amsterdam.
In 2006, the town of Wormer had 12,566 inhabitants, and 13,075 in 2020. The built-up area of the town is 16.88 km².
The town is situated in the Zaan district, on the eastern side of the river Zaan, across from Wormerveer. The town is surrounded by the nature area Wormer- en Jisperveld.
The village of Oostknollendam, the polder Schaalsmeer, the polder Enge Wormer and a part of the Markerpolder also historically belong to the area of Wormer.
Wormer, together with Engewormer, was a separate municipality until 1991, when it became a part of the new municipality of Wormerland.