Compare software

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

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