PSR (PHP Standards Recommendation)

Today, I would like to share about PSR called PHP Standards Recommendation which are also known as coding standards of PHP. Actually, PHP does not have coding rules and standards itself. Developers tend to create their code to be more maintainable & safer by using naming conventions and various coding styles. Some use frameworks like PEAR, Zend to standardize their code.

Just In Case If you don’t know about coding standards

Coding rules and guidelines ensure that software is:

  • Safe: It can be used without causing harm.
  • Secure: It can’t be hacked.
  • Reliable: It functions as it should, every time.
  • Testable: It can be tested at the code level.
  • Maintainable: It can be maintained, even as your codebase grows.
  • Portable: It works the same in every environment.

Standards are important for safety, security, and reliability.

Every development team should use a standard. Even the most experienced developer could introduce a coding defect — without realizing it. And that one defect could lead to a minor glitch. Or worse, a serious security breach.

There are four main drivers for using one:

  1. Compliance with industry standards (e.g., ISO).
  2. Consistent code quality – no matter who writes the code.
  3. Software security from the start.
  4. Reduced development costs and accelerated time to market.

In 2009, There was a conference about PHP ( At that conference, developers discussed about their opinions on working PHP projects and their complexities upon them. Finally, they decided to create coding standards to follow. The name of that association was PHP Standards Group. They updated their name as Framework Interoperability Group(FIG) later.  You can see more detail about FIG here (

Currently there are 13 approved standards.

1  Basic Coding Standard

2  Coding Style Guide

3  Logger Interface

4  Autoloading Standard

6  Caching Interface

7  HTTP Message Interface

11  Container Interface

13  Hypermedia Links

14  Event Dispatcher

15  HTTP Handlers

16  Simple Cache

17  HTTP Factories

18  HTTP Client

If you are still curious to know about other standards that are currently reviewed, draft, abandoned. Check out this official link (

By Yuuma.




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