Compare software

kalker vs fend: catalog facts
kalker	fend
Free Free and open source under the MIT licence.	Free Free and open source.
Windows, macOS, Linux, Android, Web, Command line	Command line
Natural math syntax with user-defined functions and variables Handles complex numbers, vectors and matrices	Arbitrary-precision arithmetic Built-in unit handling and conversion
Derivatives and integrals are numerical estimates Higher-order derivatives can be inaccurate	Command-line interface only, with no graphical calculator
Downloadable app, Web application	Downloadable app
Open source	Open source
License: MIT	License: MIT
No account needed	No account needed
Works offline	Works offline
Official website Full listing and sources Checked October 2, 2026	Official website Full listing and sources Checked September 24, 2026

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