--- title: Build or buy calculator: when does your replacement cost... description: This interactive calculator compares the cost of keeping a SaaS subscription versus building your own replacement, counting both cash and time. In the worked... canonical: https://daily.dev/posts/build-or-buy-calculator-when-does-your-replacement-cost-less--cyn70ujih twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Build or buy calculator: when does your replacement cost less? | daily.dev og:description: This interactive calculator compares the cost of keeping a SaaS subscription versus building your own replacement, counting both cash and time. In the worked... og:url: https://daily.dev/posts/build-or-buy-calculator-when-does-your-replacement-cost-less--cyn70ujih og:image: https://api.daily.dev/og/posts/cYN70UJIh.png og:image:alt: Build or buy calculator: when does your replacement cost less? 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. # Build or buy calculator: when does your replacement cost less? **[Flavio Copes](https://daily.dev/sources/flaviocopes)** · 6 min read · 0 upvotes · 0 comments ## Summary This interactive calculator compares the cost of keeping a SaaS subscription versus building your own replacement, counting both cash and time. In the worked example, a €80 monthly SaaS bill is compared against a replacement needing 12 hours to build plus 1 hour of monthly maintenance, with time valued at €30 an hour. With a one-month overlap running both systems, the replacement's 12-month total comes to €896 versus €960 for the subscription, a €64 saving. The break-even point lands at month eleven, where cumulative costs are €880 versus €858. The formula used is Equal-cost month = (U + B × O) / (B − R). ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How do you calculate the break-even point when deciding whether to replace a SaaS subscription with your own software? The equal-cost month is (U + B × O) divided by (B − R), where U is the initial build cost, B is the monthly cost of keeping the SaaS including your time, R is the replacement's monthly running cost including time, and O is the overlap period in months running both systems. This only works when B is greater than R, meaning the replacement is cheaper to run monthly; otherwise there's no recurring saving to repay the initial work. _Weighing a SaaS bill against building in-house? daily.dev surfaces build-vs-buy discussions from developers who've run the numbers._ ### Should I count my own time when comparing the cost of a SaaS tool versus building a replacement? Yes, time should be valued at an hourly rate and added to both sides of the comparison: the SaaS side includes hours already spent managing that product, and the replacement side includes initial build and migration hours plus ongoing maintenance hours. In one worked example, including time raised the replacement's effective monthly cost from a pure cash figure to €38 per month against an €80 subscription, with a model API or service cost of €8 counted separately. _Deciding whether to build or buy a tool? Compare real cost breakdowns on daily.dev before committing engineering hours._ ## Similar posts on daily.dev - [Build vs buy software: when AI can replace a SaaS](https://daily.dev/posts/build-vs-buy-software-when-ai-can-replace-a-saas-ck67aw8rp) · Flavio Copes · 0 upvotes · 0 comments - [Custom web application development: build vs buy](https://daily.dev/posts/custom-web-application-development-build-vs-buy-bqeoem5gt) · Netguru · 1 upvotes · 1 comments - [The Minimum Viable Unit of Saleable Software](https://daily.dev/posts/the-minimum-viable-unit-of-saleable-software-ztc5ihhp9) · Brandur Leach · 1 upvotes · 0 comments - [Is the ‘SaaSpocalypse’ a myth? The real cost of AI-built software](https://daily.dev/posts/is-the-saaspocalypse-a-myth-the-real-cost-of-ai-built-software-r5squlrt8) · The Next Web · 0 upvotes · 0 comments --- [View this post on daily.dev](https://daily.dev/posts/build-or-buy-calculator-when-does-your-replacement-cost-less--cyn70ujih) ```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":"Build or buy calculator: when does your replacement cost less?","url":"https://daily.dev/posts/build-or-buy-calculator-when-does-your-replacement-cost-less--cyn70ujih","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/build-or-buy-calculator-when-does-your-replacement-cost-less--cyn70ujih"},"datePublished":"2026-10-30T16:24:49.361Z","dateModified":"2026-10-30T16:52:50.541Z","description":"This interactive calculator compares the cost of keeping a SaaS subscription versus building your own replacement, counting both cash and time. 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Compare real cost breakdowns on daily.dev before committing engineering hours."}}]} ```