A scientific calculator is a calculator with all the arithmetic capabilities of a basic calculator plus trigonometric, statistical, logarithmic, binary logic, etc. which are useful in various scientific applications. A typical scientific calculator has some forty to fifty keys and is capable of performing about twice as many operations than that (necessitating a ``Shift'' or ``2nd'' key). They are often capable of displaying results in binary, octal and hexadecimal, but are usually limited to integers in those bases.

The calculator trigonometric functions are $\sin$ , $\cos$ , and $\tan$ , which have their own keys. The arc versions of these are usually obtainable by using the ``Shift'' or ``2nd'' key.

A scientific calculator may have a single memory register with the associated keys M+, MR and MC, but they often have several more registers to hold various values for use in statistical computations.

For values greater than about $10^{12}$ or smaller than $10^{-12}$ (slightly more or less depending on the model) hardware scientific calculators must switch to scientific notation.