What does downtime actually cost?

The direct cost of downtime is revenue lost during the outage period. But the full cost is higher: engineering time spent on incident response, SLA credits owed to customers, reputational damage, and churn from users who experience the outage. This calculator covers the quantifiable components.

How to estimate your revenue per hour

For e-commerce and transactional systems: divide annual revenue by 8,760 (hours per year). For SaaS: use MRR divided by 730 (hours per month). For ad-supported services: use hourly ad revenue. If only part of your system is affected, adjust the percentage accordingly.

Industry benchmarks: Gartner estimates average IT downtime costs $5,600 per minute across enterprise organizations. For financial services, this can exceed $100,000 per minute. For smaller SaaS companies, costs typically range from $500–$5,000 per hour.

Using this data to justify reliability investment

The incident cost calculator is most useful when building a business case for reliability investment. If a single incident costs $50,000, an SLO improvement that prevents two incidents per year justifies significant engineering investment. Compare projected incident costs against the cost of reliability improvements to quantify ROI.

See SLO Calculator and Error Budgets Explained for the framework to set meaningful reliability targets.