{{language|RPL |exec=interpreted |gc=yes |parampass=value |safety=unsafe |strength=weak |tags=rpl |hopl id=2456 |LCT=no |site=https://en.wikipedia.org/wiki/RPL_(programming_language) }}

'''RPL''' (an acronym for '''Reverse Polish Lisp''') is the onboard calculator language for the [[wp:HP 48 series|HP 48]] line of graphing calculators. It is a stack language (not a [[Lisp]]-like language, as its name implies), tightly integrated with the HP 48 system.

There are actually two languages with the name RPL: '''User RPL''' and '''System RPL'''. System RPL is used in implementing the HP 48 operating system, and User RPL is the language users use to write programs on the calculator.

The language [[RPL/2]] is a recreation of this language for POSIX machines.