What is Web Hosting Uptime? How to Measure it?

Your website is working properly and is accessible to the visitors only when your web server is running properly, server is up. Contrary, when your web server is down, your website becomes inaccessible.

Measure of uptime

Web server uptime is mostly measured in percentages, for example 99% or even 99,9%. It may seem great, but 1% downtime is about 7,2 hours per month! Sure, 0,1% downtime is even better, but this is still about 43 minutes on each month. It means that your website is not accessible to visitors and all they can see during downtime is just some kind of error message, which tells that website is inaccessible.

Why uptime is so important?

Damage of downtime may vary depending which kind of website you have. There is really not so big trouble, when small business website, which has 4-5 pages, goes down for twenty minutes now and then. It would be more troublesome with bigger business websites, which have thousands of visitors each day. Troubles with bigger website means more problems to both visitors and to the website owner. It is even worse with e-commerce sites, which are generating constant revenues - there is even possible to calculate lost revenue for each minute! 

However, when website is down, it creates bad publicity for both small and big companies - visitors see the error message, are disappointing and leaving to somewhere else. There is great risk, that they never come back.  That is why you should avoid web site hosting providers, which servers are not running properly.

Reasons causing downtime

To understand the nature of web hosting uptime better, we need to look little bit closer what may be most probable reasons causing downtime. Web hosting service consists many elements, there are servers hardware, operating systems, web server software, database components, network connections and even more tiny details, which may all fail and cause shorter or longer downtime. Best web hosting providers have usually duplicated most fragile hardware parts, like hard disks and power supply units so when one fails, another is used automatically without any downtime. Hardware becomes also more durable over time. New technology, for example SSD storage devices are offering much more reliable data storing than old fashioned hard disks. However, servers are breaking down sometimes and this is definitely making difference for overall web hosting uptime. What is important from viewpoint of choosing right web hosting provider, is that those companies, which have newer servers and more duplicated parts, have better uptime statistics than those which are using old, weared and teared servers.

There may be also software failures and network components breaking down. Good web hosting providers have also usable solutions for handling software bugs and duplicating network connections. As a rule, companies investing more to new hardware and software, hiring competent staff members, are also able to show better server uptimes.  

First thing in understanding your web hosting service provider would be to figure out how long has it been in web hosting business, what kind of servers they have, how they have systems duplicated, who is maintaining servers and what are their existing clients tell about them.

Sweet pomises

Some web hosting service providers are using term "uptime guarantee" in their marketing materials. Some web hosts are promising 99,98% and some even 99.99% uptime. Sure, it may be long term statistics measured over time, but there is also possibility that the actual performance is much worse and this is just marketing fluff. Making uptime promises is really cheapest thing web hosting providers may do and for average customer, it is quite hard to check are they really keeping their promises or not.

Besides of understanding of reasons of downtime, looking particular web hosting service provider servers, networks and staff competence, you should also read legal terms of use. Most of the web hosts may not charge you for downtime, but it is only when you know your site was down and ask explicitly for deductions on next bill. We really don't know any web hosting providers, which would offer you compensation for lost business in real value. 

How to measure uptime

We talked that web hosting providers may not always calculate uptime correctly, so you get most accurate uptime number by just monitoring website by yourself. Since most of us don't enjoy monitoring website 24 hours a day, there are simple software solutions available by neutral, third party companies. Most of these uptime monitoring services don't need any additional coding on your site, but they just ping your domain, use http page header and record monitored results to their database. Most of these uptime monitoring services don't load more components but http header of your website, so regular pinging doesn't affect visitors statistics, which are calculated with using on-page scripts. 

Depending on response code the uptime monitoring service gets from your web server, they may even send you an alert either by e-mail or SMS, so you will be notified when your website is down and when it gets up again.

Some web hosting uptime monitoring services are offering monitoring with 5 minute interval, for example uptimerobot.com and  pingdom.com, others like site24x7.com,  100pulse.com, serviceuptime.com,  siteuptime.com or  internetseer.com  have 15-60 minute intervals available as free service. Most of these web hosting uptime monitoring services are also offering upgrades to more sophisticated packages to get more detailed statistics when needed.

Conclusion

Web hosting uptime is important parameter, which describes how reliable is your web hosting service provider and how often are their servers down. The higher is uptime percentage, for example 99,99% the better it is. However you should also understand that sometimes it may be important shut servers down for short time to carry routineous maintenance tasks. Best web hosting providers are planning well ahead, sending you notification and scheduling web servers maintenance to the nighttime, when it is at least disrupting. Other web hosting companies are never notifying you ahead and are suffering unplanned server crashes during peak times. For understanding the nature of your server downtime better, you should monitor uptime with simple website monitoring services. Statistics gathered over longer time helps you to ask specific questions (for example refunds from your hosting provider) as well as make more educated decisions in selecting hosting service provider for your website.

If you are just planning to start with new web project and need good web hosting for website, see this list of UK hosts we picked based on our long term experience with number of web hosting providers. They all have excellent uptime performance, so you may register and use them with confidence.