WordPress PHP 8 Compatibility: A Comprehensive Guide for Efficient Site Management

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It’s not news that WordPress is written with the PHP scripting language. That means most of the code that powers WordPress is implemented using PHP. That includes its core functionalities, data handling, rendering of web pages, and more. So WordPress developers are always updated on the version of PHP to ensure the websites always work as expected. 

PHP Version 8 is one of the best ones for WordPress websites due to a variety of reasons. That includes a Just-In-Time Compiler (to improve the speed of PHP scripts), union types, and more. But people are often confused about whether or not PHP Version 8 would be suitable for their website.

That’s why we have created this guide to help you understand everything about PHP Version 8. Plus, its compatibility with WordPress websites.

What are the Security Risks & Vulnerabilities Associated with PHP Versions Below 8?

For WordPress development, using PHP versions below 8 poses some critical security risks and vulnerabilities. That is, in addition to the general risks associated with outdated PHP versions. As PHP is the backbone of WordPress, it’s important you’re aware of these potential issues:

  • Lack of Security Updates. Unsupported PHP versions, including those below 8, no longer receive security updates and patches. That means any newly discovered vulnerabilities in the PHP core or extensions remain unaddressed. It leaves your WordPress website exposed to potential attacks.
  • Plugin & Theme Compatibility. Some older WordPress plugins and themes might not be fully compatible with the latest PHP versions. As a result, you might need to continue using older PHP versions to maintain compatibility. That increases the risk of security issues due to the lack of updates.
  • WordPress Core Vulnerabilities. Running WordPress on outdated PHP versions might amplify certain WordPress core vulnerabilities. Vulnerabilities in the WordPress codebase can be more severe when combined with security weaknesses in older PHP versions.
  • Increased Attack Surface. Older PHP versions might have known security weaknesses. So the attackers will be able to easily exploit vulnerabilities and gain unauthorized access to your WordPress website.
  • Exposure to Known Vulnerabilities. As time passes, security researchers and attackers may discover new vulnerabilities in older PHP versions. These vulnerabilities might already have known exploits. That makes it easier for attackers to target websites using outdated PHP versions.
  • Inadequate Security Features. Older PHP versions might lack modern security features and functions. So your WordPress website will be more susceptible to common security issues. That includes cross-site scripting (XSS), SQL injection, and so many others.
  • Performance & Scalability. Older PHP versions might not offer the performance improvements and optimizations present in newer releases. It can impact the speed and scalability of your WordPress site, potentially affecting user experience and search engine rankings.
  • Compatibility with New Features. As WordPress evolves, new features and functionalities may rely on newer PHP versions or language features. Staying on older PHP versions might limit your ability to take advantage of these enhancements.

Using the latest supported PHP version is the best practice to reduce security risks and ensure optimal performance for your WordPress development projects. Before upgrading, make sure to thoroughly test your website and check plugin and theme compatibility to avoid any unexpected issues. 

Additionally, always maintain regular backups of your WordPress site to quickly restore it in case of any problems during or after the upgrade process.

Now that you are aware of security risks and vulnerabilities associated with the PHP versions lower than 8, we can go about covering how you can update it.

Relationship Between WordPress & PHP

Well, you already know the fundamental relationship between WordPress and PHP. The former is written with the latter as the base. In essence, this CMS can’t work without the scripting language. So you have to ensure the best version for compatibility and work efficiency. 

Now, although Version 8.2 is the latest of PHP, we believe Version 8 to be one of the best for WordPress websites. But how do WordPress and PHP relate? How does PHP help with WordPress website development? Let’s find out.

PHP is the Primary Language. The majority of the code that powers WordPress. That includes its core functionalities, data handling, and rendering of web pages, which are implemented using PHP. If you look at the WordPress file and directory structure, all the necessary files and folders are with the extension .php.

Server-side Execution. PHP is a server-side scripting language. That means it runs on the web server when a user requests a WordPress page. The PHP code dynamically generates HTML content and sends it to the user’s browser for display.

Dynamic Web Pages. PHP lets WordPress generate dynamic web pages to display different content based on user input, database queries, and other factors. This dynamic nature allows WordPress to create and manage various types of content. That includes blog posts, pages, categories, tags, and more.

Interaction with the Database. PHP in WordPress is used to interact with the underlying database (usually MySQL). It helps fetch, store, and update data related to the website’s content, settings, and user information.

Template System. PHP is instrumental in the template system used by WordPress to control the layout and structure of web pages. PHP templates include a mix of HTML and PHP code. That allows developers to insert dynamic content and control how data is presented on the website.

Extensibility. The PHP nature of WordPress makes it highly extensible. Developers can create custom themes and plugins using PHP to add new functionalities. They can even modify existing ones or customize the appearance of the website to meet specific requirements.

When we say, “WordPress is written with the PHP scripting language,” it means that PHP is the foundation of the WordPress platform. It empowers WordPress to be a dynamic and flexible content management system. So you can build and manage websites of all sizes and complexities.

Why Upgrade Your WordPress System to PHP 8?

Although PHP 8 isn’t the latest version of this scripting language, WordPress experts still find it one of the best. As you may expect, there are several compelling reasons and benefits behind it. That’s why if your WordPress website is still working under PHP’s Version 8, we recommend you upgrade to it.

Here are a few reasons for upgrading your WordPress system to PHP 8:

  • Performance. PHP 8 comes with significant performance improvements over previous versions. The introduction of the JIT (Just-In-Time) compiler can result in faster execution of PHP scripts. That leads to improved page load times and better overall website performance.
  • New Language Features. PHP 8 introduces several new features and improvements to enhance your coding experience. These include union types, named arguments, attributes, match expressions, and more. These features make your code more concise, readable, and maintainable.
  • Security. PHP 8 benefits from the latest security enhancements and patches. That offers a more secure environment for your WordPress website. Running your website on the latest version of PHP protects you against known vulnerabilities.
  • Long-term Support. PHP 8 is a major release with active development and long-term support. Using the latest version means you will receive ongoing updates, bug fixes, and security patches for an extended period.
  • Compatibility & Ecosystem. As PHP 8 gains popularity, more themes, plugins, and libraries are being updated and optimized for compatibility. Staying up-to-date with the latest PHP version ensures you can leverage the latest WordPress tools and resources.
  • Better Error Handling. PHP 8 improves error handling and provides more informative error messages. That helps developers quickly identify and fix issues, improving code quality.
  • Nullsafe Operator. PHP 8 introduces the Nullsafe operator (->?), making it easier to handle nullable objects. This feature can help prevent certain types of errors caused by null values.
  • Future-Proofing. Upgrading to PHP 8 future-proofs your WordPress website. As older PHP versions reach their end of life, they will stop receiving updates and security patches. So your website will be vulnerable to potential threats.

But upgrading to any new system is not a small endeavor. That’s why every WordPress development company follows a stringent process to upgrade the PHP version of their WordPress website. 

But before you upgrade the PHP version of your WordPress website, you have to understand this scripting language’s security risks and vulnerabilities.

WordPress Versions & Their Supported PHP Versions

WordPress VersionSupported PHP Versions
5.0, 5.1PHP 5.2, PHP 5.3, PHP 5.4, PHP 5.5, PHP 5.6, PHP 7.0, PHP 7.1, PHP 7.2, PHP 7.3
5.2PHP 5.6, PHP 7.0, PHP 7.1, PHP 7.2, PHP 7.3
5.3, 5.4, 5.5PHP 5.6, PHP 7.0, PHP 7.1, PHP 7.2, PHP 7.3, PHP 7.4
5.6, 5.7, 5.8PHP 5.6, PHP 7.0, PHP 7.1, PHP 7.2, PHP 7.3, PHP 7.4, PHP 8.0
5.9, 6.0PHP 5.6, PHP 7.0, PHP 7.1, PHP 7.2, PHP 7.3, PHP 7.4, PHP 8.0*, PHP 8.1*
6.1, 6.2PHP 5.6, PHP 7.0, PHP 7.1, PHP 7.2, PHP 7.3, PHP 7.4, PHP 8.0*, PHP 8.1*, PHP 8.2*

Checking the WordPress Plugin Compatibility with PHP Version 8

Let’s say you have decided to upgrade your WordPress website to PHP Version 8. Then, one of the first things you’ll need to consider is the plugins installed on the website. 

So you have to see if your WordPress plugins are compatible with PHP Version 8.

Check Plugin Information

Visit the plugin’s page on the WordPress Plugin Directory or the plugin developer’s website. Look for the plugin’s information regarding PHP version compatibility.

Check the Plugin’s Support Forum

Browse the plugin’s support forum (usually available on the Plugin Directory page) or any support resources provided by the developer. Users often discuss PHP compatibility issues and solutions in these forums.

Plugin’s GitHub or Repository

If the plugin is hosted on GitHub or another code repository, check the plugin’s repository for any recent mentions of WordPress PHP 8 compatibility. Developers often update their code to be compatible with newer PHP versions. This information can be found in the repository.

Test in a Staging Environment

Let’s say you are considering using a particular plugin on your production site. But there is no clear information about its WordPress PHP 8 compatibility. Then, consider setting up a staging environment to test the plugin with PHP 8. That lets you check for any errors or issues before implementing the changes on your live site.

Contact the Plugin Developer

There’s a chance you can’t find information about PHP 8 compatibility or you encounter issues with a plugin when using PHP 8. Then consider reaching out to the plugin developer directly. They might be aware of the issue or have plans to update the plugin for PHP 8 compatibility.

Use Compatibility Checking Tools

Some developers and hosting providers offer tools or plugins that can check the compatibility of your WordPress installation, including plugins, with different PHP versions. Look for such tools in the WordPress plugin repository, or consider using a hosting provider that offers compatibility checks.

Keep in mind that the WordPress plugin ecosystem is vast, and not all plugins may be updated immediately to support the latest PHP versions. As PHP 8 becomes more widespread, more plugins will likely be updated for compatibility. In the meantime, it’s essential to verify compatibility and choose well-maintained plugins. That ensures a smooth WordPress experience with PHP 8.If you are working with a WordPress development agency, their experts will verify the compatibility of WordPress & PHP 8, including the plugins and themes.

How to Upgrade the PHP Version in Your WordPress Website?

WordPress and PHP go hand-in-hand for any website, be it just a single page or a full-blown eCommerce store. With the above-mentioned table, you must have understood which PHP version you should have for your WordPress website. But if you have any kind of doubts regarding which version of PHP would be most suitable for your website, consult with dedicated WordPress experts. They’ll inspect your website and recommend the best option accordingly. 

So now, we can move forward to what you’re really here for. Let’s discuss how you can upgrade the PHP version of your WordPress website. 

Check Current PHP Version: Before upgrading, check the current PHP version of your hosting environment. You can find this information in your hosting control panel or by using a PHP Info plugin available in the WordPress Plugin Directory.

Backup Your Website: Before making any changes, create a complete backup of your WordPress website and database. That ensures you can restore your site in case of any issues during the upgrade process.

Verify WordPress Compatibility: Check if your current WordPress version is compatible with the PHP version you plan to upgrade to. Visit the official WordPress requirements page to ensure compatibility.

Check Theme & Plugin Compatibility: Verify that your active theme and installed plugins are compatible with the target PHP version. Visit the theme and plugin developers’ websites or the WordPress Plugin Directory to check for PHP compatibility information.

Update WordPress, Themes, and Plugins: Ensure that you are running the latest versions of WordPress, your theme, and all plugins on your website. Running up-to-date software reduces the likelihood of compatibility issues with the new PHP version.

Contact Hosting Provider: Contact your hosting provider to check if they support the PHP version you want to upgrade to. Most reputable hosting providers offer multiple PHP versions. You may be able to choose the desired version through your hosting control panel.

Change PHP Version: If your hosting provider supports the desired PHP version, access your hosting control panel. Locate the PHP settings or PHP configuration section and change the PHP version to the one you want to upgrade to. Save the changes.

Test Your Website: After upgrading the PHP version, thoroughly test your WordPress website. Check different pages, functionalities, and plugins to ensure everything is working correctly. Monitor for any errors or issues.

Monitor for Errors: Keep an eye on your website for a few days after the upgrade. Watch for any common WordPress error messages or issues arising from the new PHP version.

Resolve Compatibility Issues: If you encounter any errors or compatibility issues, refer to the theme and plugin developers’ documentation or support resources. They may provide instructions or updates to address the problems.

Review Website Performance: Check your website’s performance after the PHP upgrade. Ensure that it loads faster and performs better with the new PHP version.

Remove Backups: Once you are confident about the WordPress PHP 8 compatibility (or whichever version you find best), you can remove the backups created earlier.Remember that upgrading PHP is a significant change that can affect your website’s functionality and security. It’s crucial to test thoroughly and be prepared to revert to the previous PHP version if necessary. If you are uncertain about the process, consider seeking assistance from your host service or a WordPress website development company to ensure a smooth upgrade.

FAQs Related to WordPress PHP 8 Compatibility

What should I do if a plugin or theme is incompatible with PHP 8?
If a plugin or theme is incompatible with PHP 8, you have a few options. You may contact the plugin/theme developer for updates. The second option is to search for alternative plugins/themes with PHP 8 support. And finally, you may even consider customizing the code to make it compatible, for which you may opt for our WordPress plugin development services.
Can I downgrade PHP if there are compatibility issues with WordPress or plugins?
Downgrading PHP is possible but not recommended, as older PHP versions might have security vulnerabilities. Instead, try to resolve compatibility issues by updating plugins, themes, or custom code to be compatible with PHP 8.
Can I upgrade PHP on my own, or should I seek professional assistance?
Upgrading PHP requires technical knowledge, and any errors can impact your website's functionality. If you are not confident in performing the upgrade, it's best to seek professional assistance from your hosting provider or a WordPress developer.


WordPress and PHP go hand in hand. PHP is responsible for the functioning of every WordPress website. But more critically, upgrading the PHP version of a website means taking care of the security vulnerabilities associated with the older versions. 

Now, PHP versions 8 and above have introduced some outstanding security functionalities that can help safeguard WordPress websites from several cyber threats and attacks. So WordPress PHP 8 compatibility is key. But WordPress also includes its plugins, which should also be compatible with the particular PHP version. So check the plugin compatibility and upgrade the WordPress to PHP 8 or higher subsequently. If you are still confused about the WordPress PHP 8 compatibility or want to upgrade your website in every which way, contact our experts today!

Jigar Shah is the Founder of WPWeb Infotech - a leading Web Development Company in India, USA. Being the founder of the company, he takes care of business development activities and handles the execution of the projects. He is Enthusiastic about producing quality content on challenging technical subjects.

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