What is Uptime?

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While ‘downtime’ plays an important role in our personal lives, the professional sphere is all about uptime.

So what is uptime, and why should you care about it?

Well, whether your website sells products, informs, or entertains, you won’t be doing any of it unless you’re getting eyes on your content. And, if your website is ever down – i.e. losing uptime – then you’re missing out on opportunities to reach, engage, and convert your audience.

So read on as we unpack how uptime is calculated, what affects it, and – most importantly – how to ensure your website is maximizing it.

What is Uptime?

Uptime, at its core, refers to the amount of hours a website or online service is up and running, and available for its users to access.

Uptime is usually expressed as a percentage – 99.9% is generally considered to be both the industry standard, as well as the minimum that all websites should aim to achieve.

Uptime is a key measure of reliability and dependability, so it’s an important factor to consider not only when it comes to your own website, but when making your next software decision; whether that’s an application such as an email marketing tool, or a hosting provider for your website.

How is Uptime Calculated?

You can calculate uptime with a straightforward formula:

The amount of time available

Total time in a given period.

Let’s say, for instance, that a website is offline between the hours of 1:30am and 3am in the morning, for scheduled maintenance. We want to figure out the site’s uptime over the duration of a day, so let’s put the equation together.

24 x 60 minutes x 60 seconds = 86,400 seconds in the given time period.

Of that time, the website in this example was available for 22.5 hours of the total, which equates to 81,000 seconds.

To work out this website’s uptime over the course of that day, then, we would simply divide the amount of time it was available by the total length of the period, and then multiply the result by 100% – a sum which looks like this:

(81,000/86,400) x 100 = 94.185

This means that the website in question has an uptime of 94.185%. That’s not brilliant, but we’ll give it a pass because the time period was so short – and because it’s all hypothetical, anyway!

What Affects Uptime?

Uptime can be affected by a number of factors. Let’s take the example of an average website, for instance. What could go wrong?

  • Power outages
  • Server error
  • Domain name expiration
  • Natural disasters
  • Human error
  • Broken code
  • An old, outdated hosting plan that no longer caters to your site’s bandwidth
  • Traffic spike (Black Friday deals, anyone?)
  • Malicious Distributed Denial-of-Service (DDoS) attacks


Well, with such a cornucopia of potential hazards awaiting your site on the worldwide web, it should come as little surprise that the promised land of 100% uptime is a little unrealistic. Most techies agree that, while 99.99% is the golden ratio, 99.9% is also pretty good.

For more info, check out our guide to understand exactly why websites crash – and what you can do to keep yours up and running!

Why is Uptime Important?

Of course, uptime – as a measurement – isn’t without caveats. If a site is online, for instance, but has reduced functionality or availability, it’ll still count as ‘up’. Similarly, some companies don’t count time taken for scheduled maintenance as ‘downtime’, which can also skew the figures.

So, uptime as a calculation is one that’s somewhat open to interpretation. But in practise, uptime is vital. Not only does maintaining a solid uptime ratio send vital trust signals to your website’s users, it also means more time online: equating to more sales, more views, and more engagement with your site.

Plus, it’s not just those browsing your site’s frontend that’ll be affected by unplanned downtime – it’s your team working on the backend, too. That means uptime can also have consequences for the productivity of your site’s contributors, as well as its consumers.

Ultimately, then, uptime is important because without it, you could face:

  • The loss of customers
  • A dip in productivity
  • Damage to your site’s brand and reputation
  • Extra costs to get your site back online

No one wants any of that. So how do you give yourself the best shot at obtaining (and maintaining) near-perfect uptime?

How to Maximize Uptime

Well, firstly, that depends on where you see the biggest threats to your uptime lying. Malicious attacks? Issues with overloads caused by too much traffic? How about update installations, domain name expirations, or faulty servers?

Take a look at some of the most common blockers to achieving total uptime, summarized below – with our top tips on how to sidestep them!

Maximizing Uptime Against Malicious Attacks

Ensuring good uptime against premeditated web attacks means shoring up your site with security measures, which include:

  • Firewalls
  • Virus scanning and removal
  • Two-factor authentication
  • Reinforced DDoS protection

You should also ensure that you’re regularly updating your site, as outdated websites are more vulnerable to attacks. Securing your passwords and internet networks are also vitally important measures, as are implementing server hardening practises, too.

Maximizing Uptime Against Traffic Overloads

If your site is prone to traffic spikes (say, you’re an ecommerce business that regularly offers flash sales and limited-time discounts), your site is likely to be vulnerable from crashing, due to the sheer amount of users trying to access it at one time.

Traffic spike screenshot Google Analytics

Just picture five people trying to cram through a door at once – it doesn’t work!

To maintain as much uptime as possible, you can utilize one of the following avenues to safeguard your website against traffic spikes:

  • Use a CDN (Content Delivery Network) or data colocation service to store your website on servers around the world. This will spread the workload out across a number of different data centers – easing the burden on your own site, in addition to enabling it to load faster for users in different countries. You can also experiment with cloud hosting to achieve a similar outcome – and maybe even save yourself some cash in the process, too!
  • Pick a new hosting plan. Chances are, the traffic spikes threatening your uptime are down to a lack of bandwidth, which you can solve by upgrading to a more expensive, more storage-packed plan.
Managing an ecommerce store? Check out our guide to the top 6 ecommerce hosting providers to bag a host with industry-leading uptime.

Maximizing Uptime Against Server Issues

If your site’s excellent uptime record is being thwarted by server issues, well…that’s not your fault, right? Right?

Well, no – it’s not. But that doesn’t mean there’s nothing you can do about it.

In fact, if your site’s uptime is suffering at the hands of the unreliability of your web host’s servers, you can simply… choose a new host! Fortunately, most hosts are pretty transparent about the kind of uptime their servers offer, which makes it easy to pick one you can depend on.

Our research has shown that HostGator and SiteGround are the top picks in this area, with an average of 99.99% uptime apiece. This is closely followed by Bluehost (99.98%), InMotion (99.97%), and A2 Hosting (99.95%).

For more info about web hosting’s biggest (and most reliable) players, check out the following related reading:

We hope you enjoyed learning about uptime with us – why not drop us a line in the comments section below to let us know how you found it?

Thanks for reading. We’ll catch up with you again next time!

Written by:
I’ve written for brands and businesses all over the world – empowering everyone from solopreneurs and micro-businesses to enterprises to some of the ecommerce industry’s best-known brands: including Yahoo!, Ecwid, and Entrepreneur. My commitment for the future is to empower my audience to make better, more effective decisions: whether that’s helping you pick the right platform to build your website with, the best hosting provider for your needs, or offering recommendations as to what – and how – to sell.

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