Countdown to Doom is a text adventure game written by Peter Killworth for the BBC Micro and published by Acornsoft in 1982. It is set on the planet Doomawangara, which is coyly shortened to "Doom". An Acorn Electron version was released in 1984 but only as a ROM cartridge for the Plus 1 expansion. This was the only game released exclusively as a ROM cart for the Electron.^{[citation needed]} There are two sequels, both published by Topologika: Return to Doom and Last Days of Doom.

Countdown to Doom
Acorn Electron Cover art
Developer(s)	Peter Killworth
Publisher(s)	Acornsoft Topologika
Platform(s)	Acorn Electron, BBC Micro, Amstrad CPC, Amstrad PCW, Atari ST, RISC OS, RM Nimbus, IBM PC, ZX Spectrum
Release	1982
Genre(s)	Interactive fiction
Mode(s)	Single-player

Topologika rereleased Countdown to Doom in 1987, expanding the scope of the game by about 50%. It was published for the BBC Micro, Acorn Electron, ZX Spectrum, IBM PC compatibles, Amstrad CPC, Amstrad PCW, Atari ST, and RM Nimbus. A RISC OS version was published in a compilation with Return to Doom and Philosopher's Quest.