The loading speed of your website depends on hosting provider, server performance, location of server, bandwidth allocation in particular area, ISP and it's connection settings, clients' network settings.
By default, Joomla isn't slow but you can do a lot to optimize ait and achieve great speed for your site.
Below you will find the most essential things you can do in orer to speed up your Joomla website.
1. Keep Joomla! engine and all the extensions updated. Though, make sure to back up your website prior performing updates.
2. Enable the Joomla Compression . To do this, navigate to System> Global Configuration. Open the server tab;
3. Remove unused and unoptimized extensions, as each extension added to your website requires additional system resources.
4. Reduce your images size. Never use large photos and then scale them using HTML - it takes the browser time to scale the images and they look worse than the original.
In case your website still loads slowly, contact your hosting provider.