MLsub is a minimal language with a type system combining subtyping and parametric polymorphism with a type inference algorithm which infers compact principal types. Simple-sub is an alternative algorithm which can be implemented efficiently and is quite easier to understand. This language supports explicitly typed records which are not extensible. Here we extend Simple-sub with extensible records, meaning that we can add new fields to a previously defined record. For this we add row variables to our type language and extend the type constraint solving method of our type inference algorithm accordingly, keeping the decidability of type inference.