Mathlib
The math library of Lean 4 observed · 2026-08-28
Health v2 · maintenance only
99/100
- Activity 99
- Release rhythm 98
- Longevity 100
How is this computed?
round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-09-03. Adoption (stars, forks) is never an input.
- gap_med: 15.0
- age_days: 1942
- days_rel: 12
- days_push: 7
- n_releases_24m: 9
Adoption not part of the score
3948 stars · 1622 forks observed · 2026-08-28
What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded
Mathlib is the community-maintained mathematics library for the Lean 4 theorem prover, containing formalized mathematical theories, tactics, and programming infrastructure. It is one of the largest collections of formalized mathematics, actively developed with frequent releases.
Use cases
- formalize mathematical proofs in Lean 4
- use verified mathematical definitions and theorems in Lean projects
- learn interactive theorem proving with a tutorial project
- develop custom proof tactics on top of a large math infrastructure
- check research-level mathematics for correctness
When to choose
- you are writing Lean 4 proofs and need standard mathematical libraries
- you want to contribute to or build on the largest formalized math repository
- you need verified tactics and infrastructure for theorem proving
When to avoid
- you need a numeric computation library like NumPy rather than formal proofs
- you work in Lean 3 and have not migrated to Lean 4
- you want a CAS (computer algebra system) for symbolic computation rather than proof verification
Facets
library · maturity active
math programming-language developer-tools mathematics programming-languages education cross-platform cli lean4 theorem-proving formal-methods proof-assistant formalized-mathematics algorithms
2 sources
- readme: https://github.com/leanprover-community/mathlib4 · fetched 2026-08-28 · 7c67e2915209
- homepage: https://leanprover-community.github.io/mathlib4_docs · fetched 2026-08-29 · 57c55c33a18f
Member repositories
| Repository | Role | Health v2 |
|---|---|---|
| leanprover-community/mathlib4 | main | 99 |
| leanprover-community/mathlib3 | mirror | 10 |
For agents
markdown · JSON · MCP: product_card(name="leanprover-community/mathlib4")
Data as of 2026-08-30T08:39:29.467469+00:00 · Report a problem