The real first-year cost of adding an API — build hours, upkeep and usage together.
Developer time to build and maintain an integration usually outweighs metered usage until you scale. Once usage does dominate, model it on the API cost forecast calculator, and compare providers head-to-head on the OpenAI vs Claude vs Gemini pricing.
Free API integration cost calculator — add developer build time, monthly maintenance and usage spend into the true first-year and three-year cost of…
Three things: the upfront developer time to build and test the integration, ongoing maintenance as the API changes or breaks, and the metered usage spend itself. At low volume the human time dominates; usage only overtakes it once traffic scales, so a slightly pricier API that is faster to integrate can be cheaper overall.
Because the headline per-request price is often a small fraction of the real cost. A cheap API with poor docs, no SDK and frequent breaking changes can cost far more in engineering hours than a pricier, well-documented one. TCO — build plus upkeep plus usage — is the number that actually leaves your budget.