Precise Calculator

Precise Calculator is free, open-source Windows software for expressions, macros, complex numbers, vectors and matrices. Variables are case-insensitive and ans reuses the last result. Its tutorial documents base prefixes, zero-based matrix indexing and explicit angle-unit operators; parentheses matter because sin45^2 differs from sin(45)^2. The function reference also gives integral's n parameter two meanings: requested decimal digits below 100, or a duration in milliseconds from 100 upward. Frequently used formulas can become macros, history recalls earlier input and results can be logged. The published precision ceiling is 100,000,000 significant digits; practical resource use is unspecified.