--- title: Pixels :: Box2D | daily.dev description: Box2D uses meters, kilograms, and seconds (MKS) units rather than pixels, which can trip up developers building pixel-based games. The recommended approach is... canonical: https://daily.dev/posts/pixels-box2d-59kvju8n2 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Pixels :: Box2D | daily.dev og:description: Box2D uses meters, kilograms, and seconds (MKS) units rather than pixels, which can trip up developers building pixel-based games. The recommended approach is... og:url: https://daily.dev/posts/pixels-box2d-59kvju8n2 og:image: https://api.daily.dev/og/posts/59KVJu8n2.png og:image:alt: Pixels :: Box2D 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. # Pixels :: Box2D **[ Box2D ](https://daily.dev/sources/box2d)** · 2 min read · 0 upvotes · 0 comments ## Summary Box2D uses meters, kilograms, and seconds (MKS) units rather than pixels, which can trip up developers building pixel-based games. The recommended approach is to keep game logic entirely in MKS units and convert to pixels only when rendering, using a chosen pixels-per-meter ratio (e.g., 50 pixels per meter based on character size). Conversion formulas are given for going from pixels to meters and back, and the piece notes that isolating this conversion to rendering code improves both physics stability and reduces the chance of logic errors. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How do I convert pixels to meters for Box2D since it uses MKS units? Choose a pixels-per-meter conversion factor based on your character's size, for example 50 pixels per meter for a 75-pixel-tall character. Convert pixels to meters with xMeters = 0.02 * xPixels (1/50), and meters back to pixels with xPixels = 50.0 * xMeters. Keep game logic entirely in meters and only convert when rendering to pixels. _daily.dev surfaces practical physics-engine tips like this for developers wiring up game logic._ ### Why is my Box2D physics simulation unstable when I use pixel values directly? Box2D expects meters, kilograms, and seconds (MKS) units, so feeding it raw pixel values causes instability because the physics engine's internal tuning assumes realistic meter-scale magnitudes. Converting length values from pixels to meters before passing them to Box2D, and back to pixels only for rendering, improves simulation stability significantly. _Developers debugging jittery physics can find focused fixes like this via daily.dev._ ## Similar posts on daily.dev - [All you need to know about pixels](https://daily.dev/posts/all-you-need-to-know-about-pixels-ydeuxp4mm) · ITNEXT · 1 upvotes · 0 comments - [Death to px, long live ch\!](https://daily.dev/posts/death-to-px-long-live-ch--hw0sq1nxi) · Terence Eden · 6 upvotes · 6 comments - [A Game Developer’s Guide to Understanding Screen Resolution](https://daily.dev/posts/a-game-developer-s-guide-to-understanding-screen-resolution-bfoavry8m) · freeCodeCamp · 2 upvotes · 0 comments - [Celeste & TowerFall Physics](https://daily.dev/posts/celeste-towerfall-physics-5cgegbapn) · Lobsters · 0 upvotes · 0 comments --- Tags: [#game-development](https://daily.dev/tags/game-development) [View this post on daily.dev](https://daily.dev/posts/pixels-box2d-59kvju8n2) ```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":"Pixels :: Box2D","url":"https://daily.dev/posts/pixels-box2d-59kvju8n2","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/pixels-box2d-59kvju8n2"},"datePublished":"2026-08-23T12:16:54.476Z","dateModified":"2026-08-23T12:18:26.375Z","description":"Box2D uses meters, kilograms, and seconds (MKS) units rather than pixels, which can trip up developers building pixel-based games. 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