--- title: AutoMapper vs Mapster vs Manual Mapping in .NET 10 description: AutoMapper went commercial on July 2, 2025 - versions up to 14.0.0 stay MIT-licensed, but 15.1+ require a paid Lucky Penny Software license (free under $5M... canonical: https://daily.dev/posts/automapper-vs-mapster-vs-manual-mapping-in-net-10-rmbysux95 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: AutoMapper vs Mapster vs Manual Mapping in .NET 10 | daily.dev og:description: AutoMapper went commercial on July 2, 2025 - versions up to 14.0.0 stay MIT-licensed, but 15.1+ require a paid Lucky Penny Software license (free under $5M... og:url: https://daily.dev/posts/automapper-vs-mapster-vs-manual-mapping-in-net-10-rmbysux95 og:image: https://api.daily.dev/og/posts/rmbySUX95.png og:image:alt: AutoMapper vs Mapster vs Manual Mapping in .NET 10 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. # AutoMapper vs Mapster vs Manual Mapping in .NET 10 **[Code with Mukesh](https://daily.dev/sources/codewithmukesh)** · [@iammukeshm](https://daily.dev/iammukeshm) · 27 min read · 16 upvotes · 3 comments ## Summary AutoMapper went commercial on July 2, 2025 - versions up to 14.0.0 stay MIT-licensed, but 15.1+ require a paid Lucky Penny Software license (free under $5M revenue) and 14.0.0 carries an unpatched high-severity DoS advisory (GHSA-rvv3-g6hj-g44x / CVE-2026-32933) that now triggers an NU1903 build warning. A BenchmarkDotNet comparison on .NET 10 with the current release of each library finds Mapperly 4.3.1 fastest at 30.2ns (beating hand-written manual mapping at 34.0ns and allocating 10% less memory), Mapster 10.0.12 has slowed to ~2x manual (67.5ns), no longer faster than AutoMapper 14.0.0 (71.9ns) as it was on the 7.x line. A decision matrix covers licensing, Native AOT support, and compile-time safety, plus migration snippets and guidance on steering AI coding agents away from defaulting to AutoMapper. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### Is AutoMapper still free to use in .NET projects? AutoMapper versions up to and including 14.0.0 remain MIT-licensed and free for any use, but 15.1 and later are dual-licensed under RPL-1.5 plus a Lucky Penny Software commercial license. A free Community license covers organizations under $5 million gross annual revenue, non-profits, education, and non-production use; commercial pricing otherwise starts around $489/year for the smallest tier. _Teams weighing AutoMapper's new licensing costs against alternatives can track comparisons like this on daily.dev._ ### Is Mapster faster than AutoMapper in .NET 10? No, not on current versions. Benchmarks on Mapster 10.0.12 versus AutoMapper 14.0.0 show them statistically level at roughly 67.5ns versus 71.9ns per mapping, both about twice as slow as manual mapping. This is a reversal from the Mapster 7.4.0 era, when it benchmarked at around 50.4ns and was noticeably faster than AutoMapper. _Anyone re-evaluating mapper performance for .NET can check fresh benchmarks like this via daily.dev before trusting stale claims._ ### Does AutoMapper have a known security vulnerability in its free version? Yes, all AutoMapper versions earlier than 15.1.1, including the free MIT-licensed 14.0.0, are affected by a High severity (CVSS 7.5) denial-of-service advisory tracked as GHSA-rvv3-g6hj-g44x and CVE-2026-32933, caused by unbounded recursion that crashes the process on deeply nested input. The fix shipped only in the commercial 15.1.1 and 16.1.1 releases and was never backported, so restoring 14.0.0 now triggers an NU1903 build warning. _Developers deciding whether to freeze, pay, or migrate off AutoMapper can follow security advisories like this through daily.dev._ ## Community discussion Top comments from developers on daily.dev. **@ajaychoudhary80** · 1 upvotes > Mapperly looks increasingly compelling for .NET, especially with compile-time mapping and Native AOT support. **@amirakrari** · 0 upvotes > Yeah at first I didn't care much about the relicensing of Automapper and Mediatr. > But because my software is open source self hostable, I would require self hosters to go grab a license and add in env vars... So currently I have default locked at the latest MIT version, and you can use latest version and provide license in env var to still use latest version... yeah not optimal, I think I will switch to mapperly personally. **@agustinbarrientos** · 0 upvotes > Can the nastiest `ProjectTo` query stay SQL-equivalent after the mapper swap? DTO throughput won't expose a changed join or projection. A green microbenchmark won't catch that. ## Similar posts on daily.dev - [AutoMapper 16.0.0 and MediatR 14.0.0 Released with .NET 10 Support](https://daily.dev/posts/automapper-16-0-0-and-mediatr-14-0-0-released-with-net-10-support-ygz7ypkby) · The Barley Architect · 12 upvotes · 1 comments - [AutoMapper 15.1 and MediatR 13.1 Released](https://daily.dev/posts/automapper-15-1-and-mediatr-13-1-released-z8hwzbjhf) · The Barley Architect · 3 upvotes · 1 comments - [AutoMapper 16.2.0 and MediatR 14.2.0 Released](https://daily.dev/posts/automapper-16-2-0-and-mediatr-14-2-0-released-cqoako3z4) · The Barley Architect · 6 upvotes · 0 comments --- Tags: [#.net](https://daily.dev/tags/.net) [View this post on daily.dev](https://daily.dev/posts/automapper-vs-mapster-vs-manual-mapping-in-net-10-rmbysux95) ```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":"AutoMapper vs Mapster vs Manual Mapping in .NET 10","url":"https://daily.dev/posts/automapper-vs-mapster-vs-manual-mapping-in-net-10-rmbysux95","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/automapper-vs-mapster-vs-manual-mapping-in-net-10-rmbysux95"},"datePublished":"2026-09-03T08:06:40.100Z","dateModified":"2026-09-13T21:00:16.627Z","description":"AutoMapper went commercial on July 2, 2025 - versions up to 14.0.0 stay MIT-licensed, but 15.1+ require a paid Lucky Penny Software license (free under $5M...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/e4b413a9278ed0c76ff4fd873662b60d?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/e4b413a9278ed0c76ff4fd873662b60d?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Code with Mukesh","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Person","name":"Mukesh Murugan","url":"https://daily.dev/iammukeshm","image":"https://lh3.googleusercontent.com/a-/AFdZucr2UBIpOeVTWohK8XKuXPOutNG6hgyQMz7CYj7LEA=s100","interactionStatistic":{"@type":"InteractionCounter","interactionType":{"@type":"EndorseAction"},"userInteractionCount":510}},"commentCount":3,"discussionUrl":"https://daily.dev/posts/automapper-vs-mapster-vs-manual-mapping-in-net-10-rmbysux95","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":16},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":3}],"keywords":".net","timeRequired":"PT27M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Code with Mukesh","item":"https://daily.dev/sources/codewithmukesh"},{"@type":"ListItem","position":3,"name":"AutoMapper vs Mapster vs Manual Mapping in .NET 10"}]} {"@context":"https://schema.org","@type":"WebPage","@id":"https://daily.dev/posts/automapper-vs-mapster-vs-manual-mapping-in-net-10-rmbysux95","comment":[{"@type":"Comment","text":"Mapperly looks increasingly compelling for .NET, especially with compile-time mapping and Native AOT support.","datePublished":"2026-09-08T01:24:47.753Z","url":"https://daily.dev/posts/rmbySUX95#c-4sKVWz7Ij","author":{"@type":"Person","name":"Ajay Choudhary","url":"https://daily.dev/ajaychoudhary80","image":"https://media.daily.dev/image/upload/s--WkX8wDW2--/f_auto/v1780989706/avatars/avatar_QNZlI2SgVnNSx5PSRpCVx?_a=BAMAMiWQ0"},"interactionStatistic":{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":1}},{"@type":"Comment","text":"Yeah at first I didn’t care much about the relicensing of Automapper and Mediatr.\nBut because my software is open source self hostable, I would require self hosters to go grab a license and add in env vars… So currently I have default locked at the latest MIT version, and you can use latest version and provide license in env var to still use latest version… yeah not optimal, I think I will switch to mapperly personally.","datePublished":"2026-09-04T21:04:22.320Z","url":"https://daily.dev/posts/rmbySUX95#c-nQM8eoUk2","author":{"@type":"Person","name":"Amir Akrari","url":"https://daily.dev/amirakrari","image":"https://media.daily.dev/image/upload/s--7_CzKxRf--/f_auto/v1767743051/avatars/avatar_aElrZ8dbeZcAUjCy9rgnM?_a=BAMAK+ZW0"}},{"@type":"Comment","text":"Can the nastiest ProjectTo query stay SQL-equivalent after the mapper swap? DTO throughput won’t expose a changed join or projection. A green microbenchmark won’t catch that.","datePublished":"2026-09-08T06:02:12.660Z","url":"https://daily.dev/posts/rmbySUX95#c-HqwYAzx1R","author":{"@type":"Person","name":"Agustin Barrientos","url":"https://daily.dev/agustinbarrientos","image":"https://media.daily.dev/image/upload/s--5ayxQnqn--/f_auto/v1788281802/avatars/avatar_wQYYVe5Tbj0NJ7C7qPoa8?_a=BAMAMicg0"}}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/automapper-vs-mapster-vs-manual-mapping-in-net-10-rmbysux95#faq","mainEntity":[{"@type":"Question","name":"Is AutoMapper still free to use in .NET projects?","acceptedAnswer":{"@type":"Answer","text":"AutoMapper versions up to and including 14.0.0 remain MIT-licensed and free for any use, but 15.1 and later are dual-licensed under RPL-1.5 plus a Lucky Penny Software commercial license. A free Community license covers organizations under $5 million gross annual revenue, non-profits, education, and non-production use; commercial pricing otherwise starts around $489/year for the smallest tier. Teams weighing AutoMapper's new licensing costs against alternatives can track comparisons like this on daily.dev."}},{"@type":"Question","name":"Is Mapster faster than AutoMapper in .NET 10?","acceptedAnswer":{"@type":"Answer","text":"No, not on current versions. Benchmarks on Mapster 10.0.12 versus AutoMapper 14.0.0 show them statistically level at roughly 67.5ns versus 71.9ns per mapping, both about twice as slow as manual mapping. This is a reversal from the Mapster 7.4.0 era, when it benchmarked at around 50.4ns and was noticeably faster than AutoMapper. Anyone re-evaluating mapper performance for .NET can check fresh benchmarks like this via daily.dev before trusting stale claims."}},{"@type":"Question","name":"Does AutoMapper have a known security vulnerability in its free version?","acceptedAnswer":{"@type":"Answer","text":"Yes, all AutoMapper versions earlier than 15.1.1, including the free MIT-licensed 14.0.0, are affected by a High severity (CVSS 7.5) denial-of-service advisory tracked as GHSA-rvv3-g6hj-g44x and CVE-2026-32933, caused by unbounded recursion that crashes the process on deeply nested input. The fix shipped only in the commercial 15.1.1 and 16.1.1 releases and was never backported, so restoring 14.0.0 now triggers an NU1903 build warning. Developers deciding whether to freeze, pay, or migrate off AutoMapper can follow security advisories like this through daily.dev."}}]} ```