A sanity test or "smoke test" is a brief run-through of the main functionality of a computer program or other product. It gives a measure of confidence that the system works as expected prior to a more exhaustive round of testing.

Also, the name sanity test has been used to refer to various order of magnitude and other rule of thumb devices applied to mathematical calculations. 7382 cannot be equal to 53,874 since 3002 is 90,000; the power output of a car cannot be 700 kJ since that is a unit of energy, not power (energy per unit time) and 918 x 155 is not 142135 since 918 divides by three but the answer does not (digits do not add up to a multiple of three).