A non-transitory computer-readable recording medium storing an estimation program that causes a processor included in a computer to execute a process. The process includes receiving a message of an estimation target of a forwarding destination, searching past messages for a message similar to the received message, estimating, when there is no similar message among the past massage, the forwarding destination of the message using a model of estimating the forwarding destination based on a keyword that is identified based on a word included in the received message, and outputting a forwarding destination of the searched similar message or the estimated forwarding destination.