Compare software

Isabelle vs Idris: catalog facts
Isabelle	Idris
Best for: Researchers and students working on formal mathematical proofs and verification	Best for: Programmers exploring dependent types and verified functional programming
Free Free to download for Linux, Windows and macOS.	Free Free and open source under the BSD 3-Clause licence.
Windows, macOS, Linux	Windows, Command line
Long-established proof assistant with regular releases Bundled jEdit-based IDE with dark mode and screen reader support All 3 strengths for Isabelle Long-established proof assistant with regular releases Bundled jEdit-based IDE with dark mode and screen reader support Builds for Linux on Intel and ARM, Windows and macOS	Types are first-class and can describe precise program properties Compiler can check assumptions and proofs before the program runs All 3 strengths for Idris Types are first-class and can describe precise program properties Compiler can check assumptions and proofs before the program runs Language server and community tooling available
Large projects need a lot of memory, up to 64 GB Steep learning curve for those new to formal proof	Small ecosystem compared with mainstream languages Dependent types have a steep learning curve
Downloadable app	Downloadable app
Not open source	Open source
License not stated	License: BSD-3-Clause
No account needed	No account needed
Offline features available	Offline features available
Official website Full listing and sources Sources for Isabelle cl.cam.ac.uk/research/hvg/Isabelle Catalog checked October 2, 2026	Official website Full listing and sources Sources for Idris idris-lang.org Catalog checked October 2, 2026

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