AddUp is a Windows calculation software product produced by the operator of the Orefa.com internet web site. Two main versions exist which are developed concurrently.

Version 1 is a freeware product that emphasizes small footprint and ease of use. It can handle complex operations like: -((log(1 2) * 3)^4)% sin(56e-7) / 8. Its "tape" metaphor lets the user retain, review and recalculate past operations, copy/paste, save to file, etc. Even though it is free, it is not so-called "crippleware" but a fully functional product without any nag screen or other annoyance.

Version 2 is an advanced product released as shareware. It offers many additional features such as conversion between measurement units (metric and english, many categories), financial and scientific functions, statistics, numeric base conversions (from 2 to 36), bit-level operations, complex numbers, selectable numeric notation, and more. Features include:

• An editable work area lets you type in your calculations directly. It works like a regular text editor that lets you further process your results.

• Financial functions: future value, present value, interest rate and others.

• Exponentials functions: exp, ln, log, fact, pow, root and others.

• Fractional and whole number processing: ceil, floor, round, sRound and others.

• Random number generation, real or complex, linear or gaussian.

• Seven different numeric formats for all needs: scientific (1.23e-45), currency (12,345.00), fractional (1 2/3) and others, each formats being customizable.

• Prime number functions.

• Trigonometric and Hyperbolic functions, normal and inverse.

• Statistical functions: group attributes (max, gcd, lcm and others) and distribution values (sd, var, median and others).

• Bit-level binary functions: binary-and, binary-or, binary-shift and others.

• Units and conversions: convert feet to meters to feet to yards to inches to centimeters to miles; convert grams to ounces to pounds to kilograms to pounds; convert pints to liters to pints to quarts to gallons; convert Celsius to Fahrenheit to Celsius to Kelvin to Rankine; a large number of other units convertible in this manner.

• Numeric bases: binary, octal, hexadecimal, actually all number bases from 2 to 36 are supported in all functions and all display formats. Conversions from any numeric base to any other are supported.

• Complex numbers are natively supported and also accompanied by a specialized set of access functions.

• Annotate, edit and repeat calculations in the work area. Save all work for later use either in text (.txt) or rich-edit (.rtf) format.

• A comprehensive help file is included.