P4 may refer to:

Computing

* Intel Pentium 4, a 7th-generation processor design ** The P4 power connector introduced to power it and later CPUs in the ATX12V 1.0 standard * The i486DX (P4) model of the

Intel 80486 The Intel 486, officially named i486 and also known as 80486, is a microprocessor. It is a higher-performance follow-up to the Intel 386. The i486 was introduced in 1989. It represents the fourth generation of binary compatible CPUs following t ...

, a high-performance microprocessor * P4 (programming language), for describing packet forwarding * P4, the Perforce software command line client

Media

* P4 Radio Hele Norge (PFI), a Norwegian radio company ** Kanal 24 (Kanal 4), which acquired the Norwegian P4 channel from PFI *

Sveriges Radio P4 P4 (''pe fyra'') is a national radio channel produced by the Swedish public broadcaster Sveriges Radio. P4 was started in 1987 as a network of regional stations, but national programming was added in 1993 when P3 was relaunched as a specialist yo ...

, a Swedish radio channel * ''

Persona 4 released outside of Japan as ''Shin Megami Tensei: Persona 4'', is a 2008 role-playing video game by Atlus. It is chronologically the fifth installment in the '' Persona'' series, itself a part of the larger ''Megami Tensei'' franchise, and w ...

'', a 2008 video game * '' Periphery IV: Hail Stan'', 2019 album by American progressive metal band Periphery

Military

* Skaraborg Regiment (armoured), a Swedish army unit whose designation is P 4 * Peugeot P4, a vehicle used by the French Military

Science

* P4 laboratory, a biosafety level 4 facility * Tetraphosphorus (P₄), an allotrope of phosphorus * Group p4, the plane symmetry group Wallpaper group p4 *

Progesterone Progesterone (P4) is an endogenous steroid and progestogen sex hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species. It belongs to a group of steroid hormones called the progestogens and is the ma ...

(Pregn-4-ene-3,20-dione), a steroid hormone * Kerberos, the fourth moon of Pluto *

Perfect fourth A fourth is a musical interval encompassing four staff positions in the music notation of Western culture, and a perfect fourth () is the fourth spanning five semitones (half steps, or half tones). For example, the ascending interval from C to th ...

, an interval in music theory *

Enterobacteria phage P4 ''Enterobacteria phage P4'' (also known as satellite phage P4) is a temperate bacteriophage strain of species ''Escherichia virus P2'' within genus ''Peduovirus'' (formerly ''P2-like viruses'', ''P2virus'', and ''P2likevirus''), subfamily ''Peduo ...

* P4, an EEG electrode site according to the 10-20 system * P4 cell, a stage in the ''Caenorhabditis elegans'' embryonic development * P4 metric - performance metric of the binary classifier.

Roads

* P4 road (Latvia) * P04 road (Ukraine)

Other uses

Papyrus 4 Papyrus 4 (, part of ''Suppl. Gr.'' 1120) is an early New Testament papyrus of the Gospel of Luke in Greek. Opinions differ as to its age. It has been dated anywhere from the late second century to the fourth century. Description It is one of ...