What an Uptime Guarantee Really Means

'Uptime' isn't a hard concept to grasp - it just means how much time a particular server is able to keep things running without glitches. If a web host says they have "99% uptime", what they mean is that there are only problems with that server 1% of the time - and all the rest of the time your website will be up and running. This sounds like an amazing claim, but sadly it's hard to verify and easy to mislead with.

Perhaps they mean "this server has been up for 99% of the time since it was switched on ten years ago", which would be excellent. Perhaps, however, they mean "this server is up for 99% of every week" - which would mean you'd have downtime of more than one hour and forty seconds on a weekly basis! If the website in question is your livelihood, that's unacceptable - especially as it comes to whole three days a year.

Depending on what a company says about its uptime, you'll want to think about it carefully before you decide that it means they are to be trusted. Here are a few comparisons for you, if you're wondering what most of these claims mean in real terms:

  • 98% uptime would men you'd have to cope with your site being down for 28.8 minutes a day, 3.4 hours a week, 14.4 hours in a month or 7.3 days throughout the year.
  • 99% is of course an improvement, but you'll still be out for 14.4 minutes a day, 1.7 hours a week, 7.2 hours in a month or 3.65 days throughout the year.
  • 99.5% is getting there, but you're still going to have trouble with a site down for 7.2 minutes a day, 0.84 hours a week, 3.6 hours in a month or 1.83 days in a year.
  • 99.9% is the kind of number you're looking for. This means you're only out for as little as 1.44 minutes a day, 0.17 hours in a week, 0.72 hours in a month or 8.8 hours in a year.

It's also a good idea to think about it in terms of lost profits. If your website brings in a thousand dollars a month, you stand to lose $20 every month - or $240 in a year - from using a host with 98% uptime. You'll also suffer from customers and search engines seeing your website as unreliable and not wanting to come back to you as often as they might otherwise have done.

It's simply not possibly to find a company who can offer you 100% uptime; things happen and things go wrong and you will have trouble. You do want to look for at least 99.5%, though, if you're thinking realistically about the amounts of money you can afford to spend on making up for lost revenue. This will inevitably lead to slightly more expensive web hosting, but it won't cost you anything like as much as an extra $20 a month - which surely means it's worth it!