I saw a message suggesting I should “update PHP”. What does that mean?

This page is showing a generic answer.
To see a more detailed answer customized for you, type your domain name here:

When you use a script like WordPress on your website, it runs a software program called PHP on our servers. The PHP software interprets the programming code in the script and generates the web pages people see.

Like any other software, PHP comes in different versions. New versions are usually faster and have fewer bugs, but some scripts may require certain versions of PHP.

We let customers choose between different versions of PHP, but you should usually choose the most recent version that’s compatible with your scripts.

On this page:

I know nothing about this. What should I do?

If you’re not sure what version of PHP to choose, do this after making sure to update your scripts (including applying all WordPress plugin and theme updates):

  1. Login to the “My Account” control panel (having trouble?)
  2. Click PHP Settings
  3. Choose the version of PHP marked “recommended for most customers
  4. Click Save Settings

That’s all it takes. This combination almost always offers the best combination of security, performance, and compatibility.

After doing this, check your website and make sure it still works as it did before. if it does (it usually will), you’re finished. If it doesn’t, set the PHP version back to what it was before to make the site work properly again, and contact us for assistance.

Why do I need to update PHP?

An analogy will help explain this:

  • Scripts such as WordPress are like programs on your computer
  • PHP is like the Windows or Mac operating system on your computer

When you install new software on your computer, you need to use a reasonably modern operating system, too. You probably don’t worry about every last detail of what versions you’re using, but you might have problems if the operating system on your computer hasn’t been updated for years. For example, if you try installing the latest Microsoft Office on an old Windows XP operating system, it probably won’t work.

The same is true with scripts like WordPress, and with PHP. As you upgrade your scripts (“programs”) over time, you should also make sure you’re using a fairly recent version of PHP, the “operating system” those scripts run on.

People who create scripts usually write them to work with several different versions of PHP. But they do expect you to be using a version that’s fairly recent, not a version that’s many years old.

Fortunately, updating PHP is much easier than updating your computer operating system — you just click the button in our control panel. (And unlike computer upgrades, you can instantly click back to an older version of PHP if you have trouble.)

Why can’t I just use an old version of PHP forever?

The reason this won’t work is the same reason you can’t just use an old computer operating system (like Windows XP) forever. You’ll encounter more and more situations where things just don’t work properly.

Newer versions of PHP are generally more secure, have fewer bugs, and run your scripts more quickly. Of course, that’s really just another way of saying that older versions of PHP are insecure, buggy, and slow.

People who write scripts (including scripts like WordPress plugins and themes) generally don’t use old PHP versions and don’t test their scripts to work on those old versions. They really want you to update PHP.

If you keep using a very old version of PHP, it’s likely that your site will eventually stop working when you install a script update (like a WordPress plugin update) that nobody ever tested with that old PHP version.

Aside from that, old versions of PHP eventually get removed from our servers anyway, as described in the next section. So using an old version forever isn’t possible: your site will be switched to a newer version of PHP at some point, even if you do nothing.

Why doesn’t Tiger Technologies update PHP for me?

We want all our customers to keep their scripts updated and use recent versions of PHP. But because we don’t actually know if you’re updating your scripts to be compatible with recent PHP versions, we can’t force you to update PHP as often as we think you should update it.

For example, if you hired someone to write a custom script for you ten years ago, and you’ve never updated that script, it’s possible that switching to a newer version of PHP might cause it to stop working. (This is similar to updating your computer operating system, where old programs may not work if you haven’t updated them for many years.)

Because of that, we let people use older versions of PHP much longer than we think think they should use them — but we strongly encourage you to update both your scripts and PHP on a regular basis.

If you ignore our nagging, the PHP version on your site will eventually get “upgraded” when a very old version is entirely removed from our servers. But if that happens, you won’t have a chance to temporarily switch back to an older version of PHP if things don’t work properly. It’s far better to do it yourself, at a time when it’s convenient for you to test things afterwards.

(Also, if we did upgrade PHP for you automatically, things wouldn’t be very different. We’d still need to send you a notice similar to the one we send now, except it would say “we upgraded PHP for you and you should check your site” instead of “please upgrade PHP at a time convenient for you and check your site”. But that might mean your site goes unchecked for some time until you read the notice, especially if you’re on vacation.)

What if I update PHP and then have problems?

You probably won’t notice any change after upgrading PHP, except that your site may run a little faster. Problems are rare if you’re using scripts that have been updated recently.

Still, after you choose a newer version of PHP in our control panel, you should test your site thoroughly. If you do see any problems, switch it to the next-older PHP version in our control panel and test it again. Continue testing and choosing older versions as necessary until it’s set back to the original version if you need to go that far. Your site will again work immediately, and you can let us know the details of the trouble you had. We’ll be glad to help.

That said, almost everyone who contacts us about this simply hasn’t first updated the scripts they use, such as all their WordPress plugins and themes. Be sure to do that before you update PHP.

Are there any technical guides about the differences between versions?

The PHP authors provide guides explaining the differences between versions. However, those are mostly for programmers; you probably don’t need to worry about that level of detail.