Convert SLA percentages to real downtime: see what 99.9% vs 99.99% uptime means per year, month, and day.
Hosting companies love advertising "99.9% uptime!" — it sounds bulletproof. But what does that actually mean in hours your site is dark? This calculator converts any SLA percentage into real downtime per year, month, week, and day. The numbers surprise most people.
Two gotchas: most SLAs exclude scheduled maintenance (which can be hours monthly), and "compensation" is usually account credit, not cash. A 99.9% SLA is only as good as the host's track record — check independent uptime monitors before trusting the marketing.
For most sites, yes — it's ~43 minutes of downtime a month. For a busy store, consider 99.95%+.
Independent monitors like UptimeRobot's public reports or review sites that track long-term data. Don't rely solely on the host's status page.
Usually service credits (e.g. 10% of your monthly bill per hour of excess downtime). Read the terms — and you often have to claim it yourself.
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