--- title: How To Predict Random Numbers Generated By Computers description: Demonstrates how JavaScript's Math.random() function can be predicted by reverse-engineering the V8 engine's XORShift128 algorithm. The tutorial shows how to... canonical: https://daily.dev/posts/how-to-predict-random-numbers-generated-by-computers-tsitkbhlt twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: How To Predict Random Numbers Generated By Computers | daily.dev og:description: Demonstrates how JavaScript's Math.random() function can be predicted by reverse-engineering the V8 engine's XORShift128 algorithm. The tutorial shows how to... og:url: https://daily.dev/posts/how-to-predict-random-numbers-generated-by-computers-tsitkbhlt og:image: https://api.daily.dev/og/posts/tSITkbHLT.png og:image:alt: How To Predict Random Numbers Generated By Computers 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. # How To Predict Random Numbers Generated By Computers **[Community Picks](https://daily.dev/sources/community)** · 13 min read · 2 upvotes · 1 comments ## Summary Demonstrates how JavaScript's Math.random() function can be predicted by reverse-engineering the V8 engine's XORShift128 algorithm. The tutorial shows how to use Z3 SMT solver to find the internal state values and predict future random numbers, highlighting security vulnerabilities in applications that rely on Math.random() for cryptographic purposes. Emphasizes the importance of using cryptographically secure random number generators instead of pseudo-random generators for security-critical applications. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: --- Tags: [#security](https://daily.dev/tags/security), [#javascript](https://daily.dev/tags/javascript), [#python](https://daily.dev/tags/python), [#cryptography](https://daily.dev/tags/cryptography), [#v8](https://daily.dev/tags/v8) [View this post on daily.dev](https://daily.dev/posts/how-to-predict-random-numbers-generated-by-computers-tsitkbhlt) ```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":"How To Predict Random Numbers Generated By Computers","url":"https://daily.dev/posts/how-to-predict-random-numbers-generated-by-computers-tsitkbhlt","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/how-to-predict-random-numbers-generated-by-computers-tsitkbhlt"},"datePublished":"2025-06-03T18:45:22.668Z","dateModified":"2025-06-03T18:45:59.408Z","description":"Demonstrates how JavaScript's Math.random() function can be predicted by reverse-engineering the V8 engine's XORShift128 algorithm. 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