mypy
Static type checker for Python that detects type errors in your code.
Pricing
Free tier
Flat rate
Adoption
↗RisingLicense
Open Source
Data freshness
Verified · Jul 16, 2026Overview
What is mypy?
mypy is a static type checker for Python that helps catch type-related bugs before runtime. It checks variable types during compile time, ensuring robust and maintainable codebases.
Key differentiator
“mypy stands out as an essential tool for Python developers seeking to enhance code quality through static type checking, offering robust integration with various development environments and extensive support for gradual typing.”
Capability profile
Capability Radar
Honest assessment
Strengths & Weaknesses
↑ Strengths
↓ Weaknesses
mypy leverages Python-specific type annotations and idioms, which can be challenging for those unfamiliar with the language.
Version updates often introduce significant changes to the type system or configuration options that require substantial codebase adjustments.
mypy may not fully support some advanced Python features like metaclasses, dynamic attributes, and complex decorators, leading to false negatives or positives in type checking.
Running mypy on extensive codebases can be time-consuming and resource-intensive, potentially slowing down development workflows.
Fit analysis
Who is it for?
✓ Best for
Teams working on complex, large-scale Python applications where type safety is critical.
Developers who want to catch potential bugs before runtime by ensuring type consistency.
✕ Not a fit for
Projects that do not require static typing or prefer dynamic typing for flexibility.
Small projects where the overhead of setting up and maintaining a type checker outweighs the benefits.
Cost structure
Pricing
Free Tier
Available
Open source — free to use
Starts at
$0
Model
Flat rate
Enterprise
None
Performance benchmarks
How Fast Is It?
Ecosystem
Relationships
Integrations
Next step
Get Started with mypy
Step-by-step setup guide with code examples and common gotchas.