Depends on who you accept as God.
Matthew 5:28 "If a man looks on a woman to lust after her, he has committed adultery with her already in his heart."
Psalm 101:3 "I will set no unclean thing before my eyes."
Up to you, man.
Porn can be like an intoxicant, something that has an unhelpful effect on the mind, as can violent television programs. Read Thich Nhat Hanh for more.
"Enjoin believing men to restrain their gaze and guard their private parts. That is purer for them. Surely Allah is well aware of all what they do.
And enjoin believing women to restrain their gaze and guard their private parts and additionally not to reveal their adornment except that which is revealed of itself." Quran 24:30-31
"Surely God enjoins justice, kindness and the doing of good, to kith and kin; and He forbids all that is shameful, indecent, evil, rebellious and oppressive." Quran 16:90
Sex and porn are "the invented tools of degradation" created by psychiatrists millions of years ago to entrap us in their conspiracy.