Build vs Buy Software Calculator

The Classic Dilemma: Build or Buy?

Every CTO, engineering manager, and startup founder eventually faces this question: "We need a tool to do X. Should we pay $500 a month for this SaaS, or just have our engineers build a simple version this weekend?"

Spoiler alert: It rarely takes "just a weekend," and the hidden costs of building internal software are massive. Our calculator helps you visualize the true 3-year Total Cost of Ownership (TCO).

The Hidden Costs of Building

• Maintenance & Bug Fixes: Software rots. APIs change, dependencies break, and security vulnerabilities emerge. Even a simple internal tool requires hours of maintenance every month.
• Opportunity Cost: If your lead engineer is spending 10 hours a month maintaining an internal billing dashboard, they are not spending those 10 hours building your core product that actually makes you money.
• The "Bus Factor": If the one developer who built the internal tool leaves the company, handing over the undocumented codebase to a new hire is incredibly expensive.

When Should You Build?

Building software in-house makes sense when the tool is your core competency or provides a massive competitive advantage. If you are a logistics company, building your own proprietary routing algorithm makes sense. But building your own CRM or Chat app does not.

When Should You Buy?

Buy software for anything that is a commodity function. CRM (Salesforce), Email Marketing (Mailchimp), Authentication (Auth0), and Payment Processing (Stripe) are solved problems. Paying a monthly subscription is almost always cheaper than dedicating internal engineering resources to reinvent the wheel.