In measure theory, a branch of mathematics that studies generalized notions of volumes, an s-finite measure is a special type of measure. An s-finite measure is more general than a finite measure, but allows one to generalize certain proofs for finite measures.
The s-finite measures should not be confused with the σ-finite (sigma-finite) measures.
Let be a measurable space and a measure on this measurable space. The measure is called an s-finite measure, if there are at most countably many finite measures () satisfying