Up All Nines: What is Uptime and Why Does It Matter?

Picking the best web hosting provider is often a numbers game – you compare prices, storage space, bandwidth, and so on–numbers, numbers, numbers. But there’s one number that web hosts like to highlight, and it’s the only one you’ll ever find on the large guarantee seals on their websites: Uptime, often at 99% or more. If you believe the marketing speak, this is the only number you need to be sure that your website is in good hands. And the more “nines” in there, as people in the industry might tell you, the better.

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But is that all there is to it? If you’ve ever wondered what uptime is or why you should care about it, then you’ve come to the right place. In this article, we’ll look at what uptime means for website owners like you and give you some tips for evaluating those tricky, legalese-stuffed service-level agreements (SLAs).

What is Uptime?

Simply put, uptime is a measure of reliability. When it comes to web hosting services, uptime tells you what fraction of your web host’s operating hours are incident-free. That’s why uptime typically comes as a percentage, and that’s also why web hosting providers like to crow about an abundance of nines, from 99% all the way up to 99.999%+. A number close to 100% indicates that a web host’s servers are up almost all the time — and that means your website will be, too.

Uptime is a quick way to gauge if you’re getting your money’s worth, too. If a web host guarantees you a certain uptime percentage upfront, then you’ll know what level of availability and performance you can expect from any website you host with them. Since you can verify that promise by doing the math, it’s easier to hold your web host provider accountable.

The Fine Print: Delving into Uptime

That brings us to some of the shakier dimensions of uptime: How exactly do you do the math?

Unfortunately, nobody certifies the figures that web hosting providers give for their uptime. Since it’s a measure of performance over time, covering the web host’s services for possibly millions of websites, there’s no way for you to check their general numbers for yourself, either. At least to start with, you’re going to have to trust that these web hosting providers are giving you reliable stats.

When Does Uptime Matter?

Most web hosts promise you at least 99% uptime. That looks good enough, right? 99% is a nice, high number, and it’s close enough to 100% if you’re counting.

The Cost of Downtime

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But let’s remember that uptime measures incident-free operational hours. At 99%, that means you can expect a potential 1% of downtime, and that’s if the numbers don’t end up as underestimates. If 1% doesn’t sound like a lot, consider: that’s 14.4 minutes in a day, or 87.6 hours—nearly four days!—that your website could be down in a year.

Just think how many visitors or customers you’d lose in those 80+ hours that can’t get to your website.

That cost isn’t just in direct sales, either. Even if your site isn’t down for days at a time, you could still lose customers. Let’s say it’s just one hour each day, for seven days. In the same way that you’d switch web hosting providers if your website keeps crashing on their watch, your visitors are likely to stop coming if they get frequent (if minor) problems with your website. Would you trust a company if you can’t even be sure they’ll be working properly when you visit?

In short, downtime costs you two main things: opportunity and trust. Put that way, 1% can matter a lot.

The Cost of Uptime

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That said, don’t go chasing after those nines above all else. When it comes to web hosting, hunting down ideals like “99.999%” (or the “five nines” if you want to use industry-speak) can get very costly, very quickly. It’s not entirely implausible to have another “0” tacked onto the end of your total hosting costs for every “9” you add to “99.99%”, for example.

Besides, more nines don’t automatically make for a better web host overall. After all, no server works 100% of the time, so the occasional blip is unavoidable. You’ll have to ask yourself how important it is to minimize those unplanned blips, and how much you’re prepared to spend for that. Yes, outages are costly and inconvenient, but it’s often better to spend your money on a plan that supplies more of the resources your website needs, rather than simply getting a plan that comes with an extra “nine” of uptime.

All other things being equal, an extra fraction of a percentage usually isn’t worth a massive jump in your monthly fees.

So what uptime percentage should you look for?

In general, 99.5% guaranteed uptime is a good minimum. If you can get good guarantees for higher uptimes without having to pay an extra limb for your hosting plan, then go for it.

Wait, What’s a Good Guarantee?

Not all uptime guarantees / service-level agreements (SLAs) are created equal. Okay, so almost all of them are giant blocks of text that are hard to parse. But here are the questions you should ask.

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What gets covered?

Most web hosting providers will only cover unscheduled downtime caused by problems on their end, and only if the downtime passes a certain threshold.

Let’s say you’ve been guaranteed 99.5% uptime. That 0.5% of possible downtime amounts to 3.6 hours per month. With most hosting providers, you can expect compensation only if downtime hits or exceeds that number. So if your website happens to go down for a total of, say, 3 hours and 15 minutes for that month, you won’t get any reimbursements.

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The same is likely true for any scheduled outages. Most servers, at one point or another, will need to go offline for maintenance. Your web hosting provider will usually inform you beforehand, but that doesn’t save you from any complications that might arise during the maintenance process. Check your web host’s service-level agreement (SLA) carefully. If planned downtime goes on for longer than expected, you might not be able to secure a reimbursement, either.

Some providers set out separate guarantees for downtime caused by issues with the network, software, or server hardware. This is great because you get explicit protection for downtime regardless of the nature of the problem on your provider’s end. Some SLAs aren’t as clear-cut, so you might find yourself denied of a reimbursement just because your server was up and running even while problems with your provider’s network kept your website out of commission.

What compensation can you expect?

Most providers will compensate you with a certain amount of account credits. Usually, you’ll either get the reimbursement credited to your account, or the equivalent amount will be taken off next month’s fees.

You should look at how much you’ll get. Some providers are generous enough to credit a full month’s fees if you qualify; others will give you pro-rated credits depending on how long your website was down. Note that most providers will only reimburse hosting costs, so don’t expect your web host to pay you back the sales you might have lost while your website was down.

How do you get reimbursed?

Many hosting providers won’t automatically dole out reimbursements. This means you’ll have to file a claim yourself, providing all the details — including the amount of downtime you’re seeking compensation for. If you want accurate reimbursements, you’ll often need a way to monitor your website’s availability around the clock to be able to pinpoint when downtime occurs and how long it lasts.

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Here’s the bottom line.

Downtime can be a costly affair, and the compensation plans outlined in your hosting provider’s SLA acknowledge that. However, you can’t expect a hosting provider’s SLA to make up for all the money you might lose in the event of downtime. If an hour’s outage lost you $500 in potential sales, your provider will not pay that back — the most you can hope for, really, is a fraction of your hosting fee, which will likely amount to less than $10.

Ultimately, the value of an uptime guarantee lies more in the promise of reliability that it represents rather than in the actual amount you might get back.

Which Web Hosts Rank Best for Uptime?

Okay, okay, you might be saying, this is all good information, but which web hosts should I be using?

When it comes to uptime, gauging a web hosting provider’s performance can be tricky. As we mentioned earlier, there are no quick, standardized ways to rate a web hosting provider’s reliability. Fortunately, there are independent third parties like Comparakeet that can check in on web hosts from time to time and generate an approximation of their reliability from there.

Here are our top three picks for web hosting providers with great uptime:


HostGator has registered a solid average uptime of 99.99% in the past couple of years. That’s a pretty good number, especially if we recall our “acceptable minimum” of 99.95%.

As for guarantees, HostGator offers two kinds, and which one you get depends on the plan you’ve signed up for:

  • If you’re working with a shared hosting or reseller hosting plan, HostGator guarantees only 99.9% uptime. You’ll get one (1) month of free credit if your account fails to meet that minimum standard.
  • If you’re working with VPS hosting or dedicated server hosting plans, HostGator offers a “network guarantee” instead. Rather than a set credit return for any slips in uptime, HostGator gives you prorated credits based on how long your server is down.

If those sound like good deals to you, check out our full HostGator review. We cover not just uptime, but other aspects of their services like their pricing, customer support, and more.


Over the same period of time, SiteGround registers a slightly lower 99.98% average uptime. That’s not bad at all, however, and SiteGround dedicates more effort than most to bolstering its systems’ reliability. They even provide a handy tool for checking your website’s status in real-time, as well as features like anti-bot AI systems that actively ward off threats like DDoS attacks that can take down your website.

All of SiteGround’s plans come under the same service level agreement (SLA). SiteGround promises 99.9% uptime, on par with HostGator and many other web hosting services. If your account’s uptime dips into the 99.9% – 99.0% range, you’ll get a month of free hosting. Each percentage point lower than that adds an extra month of hosting credit to your account, too.

You can check out our full SiteGround review to learn more about their hosting services and features beyond their uptime numbers.

InMotion Hosting

InMotion Hosting, over the same period, comes in at a respectable 99.97% average uptime. This web hosting provider puts a lot of thought not just into reliability but also speed, and you can choose from a selection of data centers to ensure lower latency for your website. InMotion also gives you the option to get one (1) free physical uptime check every 30 days.

Like HostGator, InMotion Hosting offers two kinds of guarantees:

  • Shared hosting users get a free month of hosting credit if their account’s physical uptime falls below 99.999%. Take note that InMotion Hosting specifies physical uptime, which narrows things down to whether the server hosting your account has been up and running.
  • Dedicated hosting users, as with HostGator, get prorated account credits based on the amount of time that their server is down.

You can check out our full InMotion Hosting review, which digs deeper into this web hosting provider’s services and features.


Uptime gives you a general idea of a web hosting provider’s reliability. It approximates the performance of your provider’s systems, and it gives you an idea of the level of service you can expect for the websites you host with them. However, uptime isn’t the end-all measure of a web host’s value, especially once you get into the 99.99%+ territory. For most website owners, an uptime of 99.5% is a good minimum.

What matters more is the coverage from your provider’s uptime guarantee or service-level agreement (SLA). Be sure to check what instances of downtime qualify you for compensation, what steps you need to take to get a reimbursement, and how much you can expect to get from your provider. A good provider will have clear-cut rules that set out fair and reasonable compensation for all manner of service lapses on their end.

If you’re really concerned about downtime, cloud hosting’s grid or network of servers offers greater resilience and redundancy than most types of hosting. You can check out our list of the best cloud hosting providers here. In the end, though, uptime ratings have their limits–it’s the quality of accompanying service that really counts.