| OpenJDK | 2007 | — | — | — |
| Openmodelica | — | declarative programming | — | — |
| OpenMusic | — | — | — | — |
| OpenMx | 2010 | structural equation modeling | dynamic typing | — |
| OpenQASM | 2017 | — | — | — |
| OPS5 | — | functional programming | — | 2 |
| OptimJ | 2006 | object-oriented programming | — | — |
| Orc | 2004 | concurrent computing | — | — |
| Orca | 2018 | — | — | — |
| ORCA/Modula-2 | 1994 | — | — | — |
| Oriel | 1991 | procedural programming, imperative programming | — | — |
| Orwell | 1984 | functional programming | — | 1 |
| Overpass QL | — | procedural programming, imperative programming | — | — |
| Overpass XML | — | procedural programming, imperative programming | — | — |
| Oxygene | 2005 | parallel computing, object-oriented programming | — | — |
| Oz | 1991 | concurrent computing, prototype-based programming, functional programming, imperative programming, multi-paradigm programming, constraint programming, object-oriented programming | dynamic typing | 2 |
| P | 2012 | — | — | — |
| P* | 2013 | — | weak typing | — |
| P4 | 2013 | imperative programming | — | — |
| PACT | 1955 | — | — | — |
| Pan | — | declarative programming | dynamic typing, strong typing | — |
| Paradox | 1985 | — | — | — |
| ParaSail | 2009 | concurrent computing, procedural programming, structured programming, parallel computing, object-oriented programming | static typing, strong typing | — |
| PARI/GP | 1985 | — | — | — |
| Parser | 1997 | procedural programming | dynamic typing | — |
| Pascal | 1970 | structured programming, imperative programming | static typing, safe typing, strong typing | 27 |
| Pascal Script | 2000 | procedural programming, imperative programming, multi-paradigm programming, object-oriented programming | strong typing | — |
| PascalABC.NET | 2007 | object-oriented programming | — | — |
| Pawn | 1999 | — | — | — |
| PCASTL | 2008 | reflective programming, procedural programming, imperative programming | — | — |
| PEARL | 1977 | procedural programming | — | — |
| PeopleCode | — | imperative programming, multi-paradigm programming, object-oriented programming | — | — |
| Perl | 1987 | multi-paradigm programming | dynamic typing | 15 |
| Perl Data Language | 1996 | functional programming, imperative programming, array programming | — | — |
| Petr | 1999 | — | — | — |
| Pforth | — | — | — | — |
| Pharo | 2008 | reflective programming, object-oriented programming | dynamic typing | — |
| Phoenix Object Basic | — | imperative programming, component-based software engineering, object-oriented programming | — | — |
| PHP | 1995 | reflective programming, procedural programming, functional programming, imperative programming, object-oriented programming | dynamic typing, gradual typing, weak typing | 5 |
| Pic Micro Pascal | — | procedural programming | — | — |
| Pico | 1997 | reflective programming, procedural programming | — | — |
| PicoLisp | 1988 | reflective programming, procedural programming, functional programming, declarative programming, metaprogramming, object-oriented programming | dynamic typing, duck typing, strong typing | — |
| Piet | 1993 | esoteric programming | — | — |
| Pike | 1994 | procedural programming, functional programming, object-oriented programming | dynamic typing, manifest typing, static typing | — |
| PILOT | 1968 | imperative programming | — | — |
| Pipeline Pilot | — | — | — | — |
| Pixie | 2015 | functional programming | — | — |
| Pixilang | 2006 | — | — | — |
| Pizza | 1996 | generic programming | — | 1 |
| Pkl | 2024 | — | — | — |
| PL/8 | — | — | — | — |
| PL/C | 1973 | procedural programming, structured programming, imperative programming | strong typing | — |
| PL/I | 1964 | concurrent computing, procedural programming, structured programming, imperative programming | strong typing | 6 |
| PL/Java | — | procedural programming | — | — |
| PL/Lua | — | procedural programming | — | — |
| PL/M | 1973 | procedural programming, structured programming | — | — |
| PL/Perl | — | procedural programming | — | — |
| PL/pgSQL | 1998 | procedural programming | — | — |
| PL/Python | — | procedural programming | — | — |
| PL/R | 2003 | procedural programming | — | — |
| PL/Scheme | — | procedural programming | — | — |
| PL/SQL | 1992 | procedural programming | — | 1 |
| PL/Tcl | — | procedural programming | — | — |
| PL360 | 1966 | procedural programming, structured programming, imperative programming | static typing, strong typing | — |
| Plankalkül | 1942 | procedural programming | — | 1 |
| Planner | 1969 | procedural programming, logic programming | — | 1 |
| PLASMA | 2012 | — | — | — |
| PLEX | 1970 | concurrent computing, procedural programming, imperative programming | — | 1 |
| PLEXIL | 2005 | multi-paradigm programming | static typing, nominative typing | — |
| Pliant | 1999 | procedural programming, imperative programming | — | — |
| Plugdata | — | — | — | — |
| Plus | 1976 | procedural programming, structured programming, imperative programming | static typing, safe typing, strong typing | — |
| Pnuts | 1997 | object-oriented programming | dynamic typing, duck typing | — |
| Polyphonic C# | 2002 | multi-paradigm programming | dynamic typing, nominative typing | — |
| Pony | — | object-oriented programming | — | 1 |
| POP-2 | 1970 | functional programming | — | — |
| PostScript | 1982 | procedural programming, concatenative programming, multi-paradigm programming, stack-oriented programming | dynamic typing, weak typing | 1 |
| PottersWheel | — | — | — | — |
| Power Fx | — | functional programming, imperative programming, declarative programming | strong typing | — |
| PowerBASIC | 1989 | — | — | — |