ready reckoner

Etymology
.

Noun

 * 1)  A printed book or table containing precalculated values, often multiples of given amounts.
 * 2) A computer program which calculates values; an online calculator.
 * 1) A computer program which calculates values; an online calculator.
 * 1) A computer program which calculates values; an online calculator.
 * 1) A computer program which calculates values; an online calculator.