The availability of a website is measured by the percentage of a year in which the website is publicly accessible and reachable via the Internet. This is different from measuring the uptime of a system. Uptime refers to the system itself being online. Uptime does not take into account being able to reach it as in the event of a network outage.[citation needed] A hosting provider's Service Level Agreement (SLA) may include a certain amount of scheduled downtime per year in order to perform maintenance on the systems. This scheduled downtime is often excluded from the SLA timeframe, and needs to be subtracted from the Total Time when availability is calculated. Depending on the wording of an SLA, if the availability of a system drops below that in the signed SLA, a hosting provider often will provide a partial refund for time lost. How downtime is determined changes from provider to provider, therefore reading the SLA is imperative.[11] Not all providers release uptime statistics.[12] Most hosting providers will guarantee at least 99.9% uptime which will allow for 43m of downtime per month, or 8h 45m of downtime per year.
Many web hosts offer limited features in their starter packages and then expand the offerings (sometimes tremendously) for higher-tier plans. Read the small print to make sure the plan you are selecting offers what you need. If you need a site builder application to design your website, make sure that the low-cost web host you are picking actually comes with a site builder. Many of them require you to pay for the builder as a separate add-on. Website builders usually don't cost a lot of money, but if you can find a web host that includes one for free, that's money in your pocket. And, if it's integrated with your hosting service, you're more likely to have a smooth, supported experience. 

When it's time to set up shop, look for a web host that offers the aforementioned dedicated servers, as well as advanced cloud server platforms (such as Amazon Web Services or Google Cloud), custom server builds should you need it, and 24/7 customer support. Depending on your business' focus, you may need a web host that can handle pageviews or visitors that rank in the high thousands or millions. Many busy hosting plans offer an onboarding specialist that can help you get started, too.
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