The church consists of a rectangular nave with a three-sided chancel and an extended sacristy to the east. Its walls are rendered inside and out and pierced by round-arched windows. A west tower, added in 1784, is topped with a dome-like roof and a substantial lantern.
Accounts differ slightly on the church's early history: one source suggests a church existed in By parish as early as 1326, with later medieval additions including a bell tower in 1349, while another simply notes the earlier medieval church stood just south of today's building. Archaeological work in 1980 is said to have located the site of that older church.
The interior today largely reflects a 1932 restoration led by the architect Eina Lundberg, during which much of the neoclassical decoration added in the 1870s was removed. As part of these works, a pulpit dating from the first half of the 17th century, along with its canopy, was reinstated in the church.
The altarpiece, a triptych depicting the Sermon on the Mount, was painted by Gunnar Torhamn, who was also responsible for the two chancel windows and the sacristy windows. The medieval triumphal crucifix from the old church remains one of the building's most distinctive historic objects.
A separate bell tower was built nearby in 1933 to house a medieval bell. Just east of the church stands the old rectory, with its main house, wings and storehouses, the oldest parts of which date from around the same period as the present church.