--- title: You’re Doing Type Validation Wrong: A TypeScript Guide... description: This article explores the concept of runtime type validation in TypeScript and introduces the Zod library as a tool to achieve it. It also discusses the... canonical: https://daily.dev/posts/you-re-doing-type-validation-wrong-a-typescript-guide-to-runtime-validation-dcf5nrsbt twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: You’re Doing Type Validation Wrong: A TypeScript Guide to Runtime Validation | daily.dev og:description: This article explores the concept of runtime type validation in TypeScript and introduces the Zod library as a tool to achieve it. It also discusses the... og:url: https://daily.dev/posts/you-re-doing-type-validation-wrong-a-typescript-guide-to-runtime-validation-dcf5nrsbt og:image: https://api.daily.dev/og/posts/dcF5nrsBt.png og:image:alt: You’re Doing Type Validation Wrong: A TypeScript Guide to Runtime Validation 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. # You’re Doing Type Validation Wrong: A TypeScript Guide to Runtime Validation **[Medium](https://daily.dev/sources/medium_js)** · [@deleteman](https://daily.dev/deleteman) · 4 min read · 17 upvotes · 1 comments ## Summary This article explores the concept of runtime type validation in TypeScript and introduces the Zod library as a tool to achieve it. It also discusses the distinction between nominal type systems and structural type systems in TypeScript and provides a workaround to add nominal type support using branded types. Overall, the article highlights the importance of type validation and offers different approaches to implement it in TypeScript. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Community discussion Top comments from developers on daily.dev. **@apperside** · 0 upvotes > Nice article, thank you! > Just a questioni: What Is the performance impact of runtime validation? ## Similar posts on daily.dev - [Don’t just attend KubeCon \+ CloudNativeCon, Merge Forward your experience\!](https://daily.dev/posts/don-t-just-attend-kubecon-cloudnativecon-merge-forward-your-experience--l0rpp73x8) · CNCF · 1 upvotes · 0 comments - [Announcing H2 2026 KCDs](https://daily.dev/posts/announcing-h2-2026-kcds-m96goajm1) · CNCF · 1 upvotes · 0 comments - [Two months of Open Community Groups](https://daily.dev/posts/two-months-of-open-community-groups-asf52zhbs) · CNCF · 0 upvotes · 0 comments - [CNCF Unveils Schedule for KubeCon \+ CloudNativeCon Europe 2026](https://daily.dev/posts/cncf-unveils-schedule-for-kubecon-cloudnativecon-europe-2026-ikhcoa5cb) · CNCF · 2 upvotes · 0 comments - [CNCF Debuts KubeCon \+ CloudNativeCon Japan 2026 Schedule](https://daily.dev/posts/cncf-debuts-kubecon-cloudnativecon-japan-2026-schedule-xp5pyudub) · CNCF · 1 upvotes · 0 comments --- Tags: [#javascript](https://daily.dev/tags/javascript), [#typescript](https://daily.dev/tags/typescript), [#webdev](https://daily.dev/tags/webdev), [#zod](https://daily.dev/tags/zod) [View this post on daily.dev](https://daily.dev/posts/you-re-doing-type-validation-wrong-a-typescript-guide-to-runtime-validation-dcf5nrsbt) ```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":"You’re Doing Type Validation Wrong: A TypeScript Guide to Runtime Validation","url":"https://daily.dev/posts/you-re-doing-type-validation-wrong-a-typescript-guide-to-runtime-validation-dcf5nrsbt","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/you-re-doing-type-validation-wrong-a-typescript-guide-to-runtime-validation-dcf5nrsbt"},"datePublished":"2023-11-09T07:53:32.468Z","dateModified":"2025-09-06T02:31:34.692Z","description":"This article explores the concept of runtime type validation in TypeScript and introduces the Zod library as a tool to achieve it. 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