Anton Kurakin
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Build vs Buy Calculator

Compare the full cost of building internally versus buying an existing solution — including ongoing ownership, not just the initial budget.

Free calculator

Build or Buy?

This is a TCO model for an initial management comparison. Be equally honest on both sides: Build is often underestimated on maintenance, while Buy is underestimated on implementation and internal support.

Currency for every monetary field. Exchange rates are not converted.
A 3–5 year view is usually more useful than comparing only the first budget year.
Build — develop internally
Average number of engineers assigned to creating the solution during the build period.
Salary plus payroll taxes, benefits, equipment, and other direct employment costs.
Time until the first usable version can replace the purchased alternative.
Average ongoing engineering load after launch. For example, 0.5 FTE means half of one engineer's time.
Hosting, databases, monitoring, licenses, and other recurring technical costs of the internal solution.
Optional. Estimate the value of work the team is not doing while it builds the internal solution. Leave 0 if you do not want to model it.
Buy — purchase an existing solution
Total license or subscription cost for the required number of users.
Configuration, migration, training, and vendor services required at the start.
Internal or external engineering work needed to integrate the purchased product.
Team time spent on administration, integrations, configuration changes, and vendor coordination.

The calculator compares cost, not strategy. Security, compliance, time to market, roadmap control, vendor lock-in, and the strategic value of proprietary technology can matter more than the TCO difference.

Why this exists

Build vs Buy is not an argument between engineering and procurement

Internal development often looks cheaper until maintenance, infrastructure, and the opportunity cost of the team are included. Buying looks cheaper until implementation, integrations, and ongoing internal work appear in the model.

This calculator is not designed to make the decision automatically. It makes the financial part visible so the real discussion can move to speed, control, risk, and strategic value.