--- title: Python Type Checker Comparison: Typing Spec Conformance description: A comparison of Python type checkers (Pyrefly, Pyright, Mypy, Ty, Zuban) based on their conformance to the official Python typing specification. The post... canonical: https://daily.dev/posts/python-type-checker-comparison-typing-spec-conformance-yvjkxqkwd twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Python Type Checker Comparison: Typing Spec Conformance | daily.dev og:description: A comparison of Python type checkers (Pyrefly, Pyright, Mypy, Ty, Zuban) based on their conformance to the official Python typing specification. The post... og:url: https://daily.dev/posts/python-type-checker-comparison-typing-spec-conformance-yvjkxqkwd og:image: https://api.daily.dev/og/posts/yvjKxqkwD.png og:image:alt: Python Type Checker Comparison: Typing Spec Conformance og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Python Type Checker Comparison: Typing Spec Conformance **[Hacker News](https://daily.dev/sources/hn)** · 6 min read · 1 upvotes · 0 comments ## Summary A comparison of Python type checkers (Pyrefly, Pyright, Mypy, Ty, Zuban) based on their conformance to the official Python typing specification. The post explains what the typing spec conformance test suite measures, how false positives and false negatives are counted, and presents a results table as of early March 2026: Pyright leads at 97.8%, followed by Zuban (96.4%), Pyrefly (87.8%), Mypy (58.3%), and Ty (53.2%). It also discusses what conformance doesn't capture, including type inference behavior, type narrowing, and experimental features, and suggests other factors to consider when choosing a type checker. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Pyrefly 1.0: A fast, forward-looking Python linter](https://daily.dev/posts/pyrefly-1-0-a-fast-forward-looking-python-linter-k4vukcqpr) · InfoWorld · 0 upvotes · 0 comments --- Tags: [#python](https://daily.dev/tags/python) [View this post on daily.dev](https://daily.dev/posts/python-type-checker-comparison-typing-spec-conformance-yvjkxqkwd) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Python Type Checker Comparison: Typing Spec Conformance","url":"https://daily.dev/posts/python-type-checker-comparison-typing-spec-conformance-yvjkxqkwd","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/python-type-checker-comparison-typing-spec-conformance-yvjkxqkwd"},"datePublished":"2026-03-16T22:09:50.855Z","dateModified":"2026-03-16T22:10:16.379Z","description":"A comparison of Python type checkers (Pyrefly, Pyright, Mypy, Ty, Zuban) based on their conformance to the official Python typing specification. 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