Precision

Precision[x] gives the number of digits of precision in the number x.

If x is not a number, Precision[x] gives the minimum value of Precision for all the numbers that appear in x.

Precision gives Infinity when applied to exact numbers, such as integers.

Precision gives $MachinePrecision for machine-precision numbers.

See The Mathematica Book: Section 3.1.4.

See also: Accuracy, N, Chop, SetPrecision, MachineNumberQ.

Further Examples