Windows Calculator goes open-source, using arbitrary-precision arithmetic for the simple stuff and Taylor series for roots and transcendental functions. : r/calculators
GitHub - 607011/bincalc: Arbitrary precision calculator with web UI (uses BigInt)
Data Structures Projects | Arbitrary Precision Calculator (APC) Project
calc: C-style arbitrary precision system download | SourceForge.net
Precise Calculator download | SourceForge.net
Precise Calculator Download: Scientific calculator with arbitrary decision, text input, prime numbers, divisors, constants, measurement units, editable variables, and more