Sales

Conflicting figures exist on the sales of Doom and Doom II.

The year 2000 edition of The Complete Wargames Handbook provides figures for the best selling computer games between 1993 and 1999. It puts Doom II as number three, with 1.5 million copies (behind Myst with 4.2 and Microsoft Flight Simulator with 2.8). Doom ends up number 8, with 1.1 million, and Ultimate Doom number 20, at 788,000. 

According to The Page of Doom, Doom II had "an initial release of over 0.5 million, and 2 millions sold to this day".

According to figures from research firm PC Data, "Doom has sold only 2.9 million units since its release in 1994". This figure is probably meant to include both Doom and Doom II, Doom and Ultimate Doom, or some other combination. The numbers do not add up to those provided by The Complete Wargames Handbook, which total at 3.4 million. A PC Data list for January 1993–April 1998 puts the sales for Doom II at 1,815,882 and "Doom Shareware" at 1,361,943, at the positions 3 and 4. Unfortunately, PC Data no longer exists, and its results were proprietary.

According to PC Magazine, June 27, 1995, Doom II was the second best selling CD-ROM game of 1994