Many PHP developers need to send email from their code. The only PHP function that supports this is [`mail()`](https://www.php.net/manual/en/function.mail.php). However, it does not provide any assistance for making use of popular features such as encryption, authentication, HTML messages, and attachments.
Formatting email correctly is surprisingly difficult. There are myriad overlapping RFCs, requiring tight adherence to horribly complicated formatting and encoding rules – the vast majority of code that you'll find online that uses the `mail()` function directly is just plain wrong!
*Please* don't be tempted to do it yourself – if you don't use PHPMailer, there are many other excellent libraries that you should look at before rolling your own. Try [SwiftMailer](https://swiftmailer.symfony.com/), [Zend/Mail](https://zendframework.github.io/zend-mail/), [ZetaComponents](https://github.com/zetacomponents/Mail) etc.
The PHP `mail()` function usually sends via a local mail server, typically fronted by a `sendmail` binary on Linux, BSD, and macOS platforms, however, Windows usually doesn't include a local mail server; PHPMailer's integrated SMTP implementation allows email sending on Windows platforms without a local mail server.
This software is distributed under the [LGPL 2.1](http://www.gnu.org/licenses/lgpl-2.1.html) license, along with the [GPL Cooperation Commitment](https://gplcc.github.io/gplcc/). Please read LICENSE for information on the software availability and distribution.
PHPMailer is available on [Packagist](https://packagist.org/packages/phpmailer/phpmailer) (using semantic versioning), and installation via [Composer](https://getcomposer.org) is the recommended way to install PHPMailer. Just add this line to your `composer.json` file:
If you want to use the Gmail XOAUTH2 authentication class, you will also need to add a dependency on the `league/oauth2-client` package in your `composer.json`.
Alternatively, if you're not using Composer, copy the contents of the PHPMailer folder into one of the `include_path` directories specified in your PHP configuration and load each class file manually:
If you're not using the `SMTP` class explicitly (you're probably not), you don't need a `use` line for the SMTP class.
If you don't speak git or just want a tarball, click the 'zip' button on the right of the project page in GitHub, though note that docs and examples are not included in the tarball.
PHPMailer 5.2 (which is compatible with PHP 5.0 - 7.0) is no longer being supported, even for security updates. You will find the latest version of 5.2 in the [5.2-stable branch](https://github.com/PHPMailer/PHPMailer/tree/5.2-stable). If you're using PHP 5.5 or later (which you should be), switch to the 6.x releases.
The biggest changes are that source files are now in the `src/` folder, and PHPMailer now declares the namespace `PHPMailer\PHPMailer`. This has several important effects – [read the upgrade guide](https://github.com/PHPMailer/PHPMailer/tree/master/UPGRADING.md) for more details.
While installing the entire package manually or with Composer is simple, convenient, and reliable, you may want to include only vital files in your project. At the very least you will need [src/PHPMailer.php](https://github.com/PHPMailer/PHPMailer/tree/master/src/PHPMailer.php). If you're using SMTP, you'll need [src/SMTP.php](https://github.com/PHPMailer/PHPMailer/tree/master/src/SMTP.php), and if you're using POP-before SMTP, you'll need [src/POP3.php](https://github.com/PHPMailer/PHPMailer/tree/master/src/POP3.php). You can skip the [language](https://github.com/PHPMailer/PHPMailer/tree/master/language/) folder if you're not showing errors to users and can make do with English-only errors. If you're using XOAUTH2 you will need [src/OAuth.php](https://github.com/PHPMailer/PHPMailer/tree/master/src/OAuth.php) as well as the Composer dependencies for the services you wish to authenticate with. Really, it's much easier to use Composer!
If you are re-using the instance (e.g. when sending to a mailing list), you may need to clear the recipient list to avoid sending duplicate messages. See [the mailing list example](https://github.com/PHPMailer/PHPMailer/blob/master/examples/mailing_list.phps) for further guidance.
PHPMailer defaults to English, but in the [language](https://github.com/PHPMailer/PHPMailer/tree/master/language/) folder you'll find many translations for PHPMailer error messages that you may encounter. Their filenames contain [ISO 639-1](http://en.wikipedia.org/wiki/ISO_639-1) language code for the translations, for example `fr` for French. To specify a language, you need to tell PHPMailer which one to use, like this:
We welcome corrections and new languages - if you're looking for corrections to do, run the [PHPMailerLangTest.php](https://github.com/PHPMailer/PHPMailer/tree/master/test/PHPMailerLangTest.php) script in the tests folder and it will show any missing translations.
Start reading at the [GitHub wiki](https://github.com/PHPMailer/PHPMailer/wiki). If you're having trouble, this should be the first place you look as it's the most frequently updated.
Examples of how to use PHPMailer for common scenarios can be found in the [examples](https://github.com/PHPMailer/PHPMailer/tree/master/examples) folder. If you're looking for a good starting point, we recommend you start with [the Gmail example](https://github.com/PHPMailer/PHPMailer/tree/master/examples/gmail.phps).
Note that in order to reduce PHPMailer's deployed code footprint, the examples are no longer included if you load PHPMailer via Composer or via [GitHub's zip file download](https://github.com/PHPMailer/PHPMailer/archive/master.zip), so you'll need to either clone the git repository or use the above links to get to the examples directly.
You can generate complete API-level documentation by running `phpdoc` in the top-level folder, and documentation will appear in the `docs` folder, though you'll need to have [PHPDocumentor](http://www.phpdoc.org) installed. You may find [the unit tests](https://github.com/PHPMailer/PHPMailer/tree/master/test/phpmailerTest.php) a good source of how to do various operations such as encryption.
If the documentation doesn't cover what you need, search the [many questions on Stack Overflow](http://stackoverflow.com/questions/tagged/phpmailer), and before you ask a question about "SMTP Error: Could not connect to SMTP host.", [read the troubleshooting guide](https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting).
There is a PHPUnit test script in the [test](https://github.com/PHPMailer/PHPMailer/tree/master/test/) folder. PHPMailer uses PHPUnit 4.8 - we would use 5.x but we need to run on PHP 5.5.
PHPMailer versions prior to 5.2.22 (released January 9th 2017) have a local file disclosure vulnerability, [CVE-2017-5223](https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2017-5223). If content passed into `msgHTML()` is sourced from unfiltered user input, relative paths can map to absolute local file paths and added as attachments. Also note that `addAttachment` (just like `file_get_contents`, `passthru`, `unlink`, etc) should not be passed user-sourced params either! Reported by Yongxiang Li of Asiasecurity.
PHPMailer versions prior to 5.2.20 (released December 28th 2016) are vulnerable to [CVE-2016-10045](https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-10045) a remote code execution vulnerability, responsibly reported by [Dawid Golunski](https://legalhackers.com/advisories/PHPMailer-Exploit-Remote-Code-Exec-CVE-2016-10045-Vuln-Patch-Bypass.html), and patched by Paul Buonopane (@Zenexer).
PHPMailer versions prior to 5.2.18 (released December 2016) are vulnerable to [CVE-2016-10033](https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-10033) a critical remote code execution vulnerability, responsibly reported by [Dawid Golunski](http://legalhackers.com/advisories/PHPMailer-Exploit-Remote-Code-Exec-CVE-2016-10033-Vuln.html).
If you have git clones from prior to the move to the PHPMailer GitHub organisation, you'll need to update any remote URLs referencing the old GitHub location with a command like this from within your clone:
Other contributions are gladly received, whether in beer 🍺, T-shirts 👕, Amazon wishlist raids, or cold, hard cash 💰. If you'd like to donate to say "thank you" to maintainers or contributors, please contact them through individual profile pages via [the contributors page](https://github.com/PHPMailer/PHPMailer/graphs/contributors).