How much does one hour of downtime cost your business?

The numbers quoted in vendor decks — "$300,000 per minute for big retailers" — are real but useless: they're about companies whose hour moves more money than a small business sees in a year. Here is the version you can actually compute, with your own numbers, in five minutes.

The honest formula

Hourly cost ≈ (revenue lost per hour) + (support cost) + (reputation cost)

• Revenue lost: monthly online revenue ÷ 730 hours. A store doing €15,000/month online loses about €20 for every hour down — more if the outage lands on your peak hours, which outages love to do.
• Support cost: tickets during an outage × average handling time × hourly cost of your team. Even 15 tickets at 10 minutes each is half a person-hour of paid firefighting.
• Reputation cost: the softest number and the biggest one. Users who saw "connection refused" don't come back today — some never do. A reasonable proxy: 2–5% of the users affected during an outage are users you paid to acquire, twice.

Two worked examples

Small services business (lead generation, €8,000/month from the site): revenue at risk is small per hour, but every lead hour lost is a customer who called a competitor instead. One lost contract dwarfs a decade of monitoring bills.

Small e-commerce (€15,000/month): €20/hour direct, but concentrated — 40% of it lands between 8pm and 11pm, exactly when deploys go wrong and cache bugs bite. A Friday-evening outage costs €80–120 directly, plus the support inbox on Saturday morning.

What monitoring actually buys you

Monitoring doesn't prevent downtime — nothing does. What it changes is how long it lasts and who tells you. The difference between knowing in 60 seconds and knowing in 4 hours (when a customer emails) is usually the difference between a blip and a lost day. For a business doing €15,000/month online, one prevented hour of Saturday downtime pays for two years of SiteFlux Business. One prevented hour pays for a decade of the €2.99 plan.

The decision isn't really "can I afford monitoring" — it's "how do I find out my site is down". The answer to the second question is about three minutes of setup away.