Server Downtime Cost Calculator
Calculate the financial cost of server or website downtime based on revenue, traffic, and hours affected.
What Is Downtime Cost? Every hour your server or website is down, you lose both direct revenue and the cost of staff time spent on the incident. This calculator estimates the full financial impact of an outage — from lost transactions to engineer hours.
The Formula Revenue per hour = Monthly Revenue ÷ (30 × 24) Lost Revenue = Revenue per Hour × Downtime Hours × (Traffic Loss % ÷ 100) Staff Cost = (Downtime Hours + Recovery Hours) × Hourly Staff Rate Total Cost = Lost Revenue + Staff Cost
SLA Downtime Allowances (per year) Different service level agreements allow different amounts of downtime:
- 99.9% uptime (“three nines”) → 8.76 hours/year (~525 minutes)
- 99.95% uptime → 4.38 hours/year (~263 minutes)
- 99.99% uptime (“four nines”) → 52.6 minutes/year
- 99.999% uptime (“five nines”) → 5.26 minutes/year
Key Insight For high-traffic sites, even a single hour of downtime can cost thousands of dollars. Investing in redundant infrastructure is usually far cheaper than the cost of a major outage.