There are many thousands of free themes for WordPress, but they are not all created equal. We would say as WP developers that a great many of them are quite old, not updated since initial release, and are no longer compatible with the latest version of WordPress CMS.
Here we offer some helpful suggestions from Theme4Press for what to look out for when trying to find a good free theme to use on a WordPress-based web site. We hope you find this post useful.
Choose a Reliable Source
You would be surprised how many WordPress themes are offered from WordPress theme sites that rank high in Google but nevertheless have malicious malware-type code included inside the theme itself.
There are ways to test a free theme for this, but honestly that is more trouble than it's worth in many cases. The easier solution is to build up a list of reputable WP theme providers that have been in business for a period of years (not a site that just sprung up last week!) to source your latest theme download.
Sites like WooThemes, ThemeForest, and Theme4Press have all been around for years and offer both free and premium themes. Trusted sources like these ensure you won't add a theme to your WordPress installation that does more than you expect.
A free theme from a developer that also offers either a premium version of the same theme with more features or other premium themes in their catalog is likely to be a good choice.
The reason is that their incentive is to demonstrate their lovely themes by offering a free theme, then perhaps you'll purchase a premium one later. Therefore, they're incentivized to do a good job with the free theme.
With a provider that only offers free themes, you have to question what their motives are? How do they fund their development expenses or value their time?
The latest free themes will include responsive design principles that make the theme morph into different appearances depending on the size of the viewing screen. This makes a responsive theme the one to pick if you expect many mobile visitors to your site.
Older free themes that were made two+ years ago often didn't include responsive features (it's only become popular in the last 12-15 months) and likely haven't been updated since as the original developer has moved onto other things since then.
The best free themes include one or more graphical sliders. This allows you to add your own images, some captions, and set animation effects. Then put this all together in a slideshow near the top of the home page to showcase a sale, new product release or your best sellers last month.
Thoughtful Widgets & Plugins
The usual widgets and plugins like a Related Posts or a Recent Posts widget may be included with a free theme. Occasionally, a developer who has access to a developer license for a particular premium plugin or widget may include this extra too.
It is quite unusual to include one or more premium features on a free theme, but the developers who choose to do so are worth watching out for. They likely take a long-term view with acquiring new customers who may try their free themes, but later purchase a premium one from them too, so they are quite likely to treat their customers with more care and include nice little extras.