When a website doesn’t open in your browser, something might be up with connection. However, the website might also be down. You can check if a website is down or not with Websitedown.info.
Websitedown is a handy website that checks the status of sites. Click here  to open the Websitedown page in shot below. It includes a text box where you can input a website to check.
Note that you don’t have to enter a full URL in the text box. You can input something like codez4mac.com. Input the URL and press the check button beside the text box.
In the shot above the website entered is down. So the page states that the website is down, and provides a summary of some of the factors behind it. It states the server might be down or undergoing maintenance.
There are a few suggestions for getting the site up further down the page. Click the show options beside tips such as User Reports and Wait a few minutes for further details. That provides additional details as in the snapshot below.
This is a handy website that makes it clear if a site is down or not. There are also alternative tools such as websitenotworking.com , downrightnow.com  and isitdownrightnow.com  that provide further details.