Domain-specific speech recognizer generation with crowd sourcing is described. The domain-specific speech recognizers are generated for voice user interfaces (VUIs) configured to replace or supplement application interfaces. In accordance with the described techniques, the speech recognizers are generated for a respective such application interface and are domain-specific because they are each generated based on language data that corresponds to the respective application interface. This domain-specific language data is used to build a domain-specific language model. The domain-specific language data is also used to collect acoustic data for building an acoustic model. In particular, the domain-specific language data is used to generate user interfaces that prompt crowd-sourcing participants to say selected words represented by the language data for recording. The recordings of these selected words are then used to build the acoustic model. The domain-specific speech recognizers are generated by combining a respective domain-specific language model and crowd-sourced acoustic model.