The uptime guarantee is the second type of guarantee that is used very often by the web hosting companies (the first is the money back guarantee).
Initially it sounded to me like a very good concept and I thought it was a good criterion to select between hosting companies. That however, was a very long time ago. Today I don't think an uptime guarantee is really worth much and I'll explain you why.
The initial thought when you hear about a 99.9% uptime guarantee is: "My website will be up 99.9% of the time!"
I'm sorry to disappoint you but that's not it! An x% uptime guarantee means that the web hosting company will strive to achieve that level of uptime and, in case it does not succeed, it will compensate you.
Typical problems
There are times when they don't mention the type of compensation. Basically that means there's no real uptime guarantee. It's just a marketing ploy.
That's an extreme case however. Usually a compensation is stipulated, but the compensation is limited to the amount that you paid for the hosting service and you have to ask for the compensation. If the uptime guarantee stated 99.9% uptime and the real uptime was 89.9%, you will not be billed for those 10% that they were not able to achieve.
Another type of compensation is a free month of hosting, which is more generous that the first type, but not really meaningful as you'll see later in this article. Yet another type is X% off the price for every extra hour of downtime, but not more than 100% of the price you paid.
Considering the fact that most uptime guarantees are given on a monthly basis, if your website was down 10% of the time, it means if was down for about 3 days. If you run a decently visited website, a 10% downtime costs you (in lost sales/sign-ups or whatever) way more than the monthly cost of web hosting.
Now lets take the most often practiced uptime guarantees and see what they really mean. A 99.5% uptime guarantee means that your website can be down for as much as 216 minutes in a month; 99.8% uptime guarantee -- 86.4 minutes of downtime; 99.9% uptime guarantee -- 43.2 minutes of downtime; 99.99% uptime guarantee -- 4.32 minutes of downtime; 99.999% uptime guarantee -- 0.432 minutes (26 seconds).
The only ones that are worth something, by that saying they promise something that would be really nice to have, are the ones promising over 99.9% of uptime. In the other cases, the downtime that can accumulate is too big to consider that we're dealing with a special accomplishment from the part of the web hosting company. That's just my opinion however. You may feel differently.
No matter what the numbers are, we can conclude rapidly that the uptime guarantee doesn't really guarantee anything. If you run a successful business, you're largely under compensated anyway, so an uptime guarantee isn't worth much, if anything.
The mistake most of us do is to think that an uptime guarantee actually guarantees anything. All it says is that you'll be somehow compensated for excessive downtime. It's just a monetary guarantee. Just like when you buy a piece of electronic equipment with a 3 years guarantee. You're not being told that the thing will function flawlessly for 3 years in a row; you're told that if it breaks, they'll repair or replace it at no cost to you.
Then why do uptime guarantees exist anyway?
Taking the story to the other side of the fence, we can easily see the benefits that a web hosting company can have if it uses an uptime guarantee. If you ever thought they're doing you a favor I'm sorry to disappoint you, but you were wrong. As with almost anything, a business seeks its own benefit, whether that's financial gain, customer's good will or an edge over the competition.
With a carefully thought uptime guarantee, a web hosting company can gain all those things with little real risk. If a downtime of 1 hour shall occur, out of 100 customers, less than 50 will ever notice. Out of those 50 about 20 will be concerned about it. Out of the 20 only about 10 will ever bother enough to call and complain about it. And out of those 10, 8 will be happy just to hear that the web hosting company is doing something about it. That usually leaves 2 customers out of 100 who will actually ask for a form of compensation. Sure, those are made-up numbers, but roughly that's how things work.
Another thing is that most web hosting companies (in their TOS) exclude downtime caused by exceptional events as earthquakes, hurricanes, DDOS attacks etc. from their uptime guarantee. Sometimes they even exclude the time when they work on the server for upgrades, or the downtime caused by software issues. This opens the gate for abuse because they can claim upgrades or software problems every time a downtime occurs.
There are of course companies going as far as excluding downtime caused by any hardware of software problems. It's like me saying that I guarantee you will not brake your leg as long as NOTHING touches it except air. Would you consider that a guarantee?
Anyway, as long as under 5% of the customers ask for compensation (and are accorded the compensation), the web hosting company usually makes a good deal out of offering an uptime guarantee. They definitely get an edge over the competition (companies not offering an uptime guarantee), they close more sales (financial gain) and they also gain customer good will because most people are impressed by a 99.99% uptime guarantee and take it as a sign of seriousness.
So, from a marketing point of view, an uptime guarantee is definitely worth the risk. This is why we'll keep on seeing it offered (even in bold letters).
There are some web hosting company owners who don't use it because they don't like using what they feel as deceiving marketing techniques. Interestingly, these are often the companies with servers consistently having a 99.9% or better uptime. They just feel it's not fair to guarantee something that's not always achievable because it gives the customer a false sense of security.
There are also some web hosting companies, very few indeed, that offer an uptime guarantee and actually notify all their customers if the established limit wasn't met and, of course, they compensate everyone for it, automatically. That's the best uptime guarantee you can get.
The ultimate uptime level - 100% - is it for real?
Now there's is a certain type of uptime guarantee that is really deceiving. That's the 100% uptime guarantee. Such a claim screams "hype". 100% uptime is simply impossible to achieve. 99.999999% uptime might be achieved, but 100% not. It's just a matter of life. Nothing is really 100%. I'll stop here and not go any further. I see no point in doing that. It's easy to understand why 100% is not achievable. Just use your imagination and remember that things in life often defy even our wildest dreams.
The uptime guarantee in itself is not a bad thing. But the way it is presented by most hosting companies is deceiving. They make it look like you will definitely enjoy consistent 99% or whatever uptime. Instead they should educate the unaware customer what that guarantee really means.
My approach
You want to how I'd go about this uptime guarantee thing? I would completely forget about the uptime guarantee. If the website is not for your business, a 95% actual uptime (which is easily achievable) is not really bad, so the uptime guarantee is not a must anyway.
If we're talking about a business website, then the loss in sales or commissions for the time when the website was down is usually important and often not fully (or not even nearly) compensated by the hosting company (even if you get a free month of hosting). Always keep in mind that a hosting company is not an insurance company.
So, for a business website, I would rely on the company's actual uptime history, which, unfortunately, can be hard to find. You can ask the hosting company for it, but there's a high chance you'll not be told the truth if the truth is embarrassing for them. I would recommend getting in contact with the clients who have posted reviews and ask them what the uptime has been over the months or years they've had their website(s) hosted there. That should be a good measure.
Now sure there are topnotch hosting solutions, the type that big business websites use, which could indeed guarantee a certain level of uptime due to a high degree of redundancy. Those however are ultimate hosting solutions, the kind that only the Yahoos and the Googles of the Internet can afford. For us the little guys, uptime guarantees come in a completely different flavor.
Hoping that you understood my point, I wish you to find such superb hosting with great uptime. So great that you'll never even have to think about that a compensation for downtime! That's what I wish you.
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