PHP has powered the web for over three decades, evolving from a simple set of CGI scripts to one of the most widely used server-side programming languages. As of 2026, PHP powers approximately 77% of all websites with a known server-side language, including major platforms like WordPress, Facebook, and Wikipedia. This comprehensive guide traces PHP complete version history, highlighting the revolutionary features, performance improvements, and security enhancements that have shaped modern web development.
The Birth of PHP: From Personal Home Page to Professional Hypertext Preprocessor
PHP journey began in 1994 when Danish-Canadian programmer Rasmus Lerdorf created a collection of Common Gateway Interface (CGI) binaries written in C. Originally designed to track visits to his online resume, these scripts quickly evolved into something far more significant.
The acronym PHP initially stood for Personal Home Page, reflecting its humble origins. As the language matured and gained professional adoption, PHP was retroactively renamed to PHP: Hypertext Preprocessor, creating a recursive acronym that developers still appreciate today.
Complete PHP Version Timeline
PHP Version
Release Date
End of Life
Key Features
1.0
June 8, 1995
–
Basic CGI scripting
2.0 (PHP/FI)
November 1, 1997
–
Form handling, HTML embedding
3.0
June 6, 1998
October 20, 2000
Zend Engine, OOP support
4.0
May 22, 2000
June 23, 2001
Zend Engine 1.0, superglobals
5.0
July 13, 2004
September 5, 2005
Zend Engine II, PDO
5.6
August 28, 2014
December 31, 2018
Constant expressions, phpdbg
7.0
December 3, 2015
December 3, 2018
2x performance, scalar types
7.4
November 28, 2019
November 28, 2022
Typed properties, arrow functions
8.0
November 26, 2020
November 26, 2023
JIT compilation, union types
8.1
November 25, 2021
December 31, 2025
Enums, fibers, readonly
8.2
December 8, 2022
December 31, 2026
Read-only classes, DNF types
8.3
November 23, 2023
December 31, 2027
Typed class constants, json_validate
8.4
November 21, 2024
December 31, 2028
Property hooks, asymmetric visibility
8.5
November 20, 2025
December 31, 2029
Pipe operator, URI extension
Early PHP Versions (1995–2000)
PHP/FI 1.0 (June 1995)
The first public release of PHP consisted of CGI tools that Rasmus Lerdorf shared with the developer community. Written entirely in C as a replacement for Perl scripts, PHP/FI 1.0 provided basic functionality for web development:
Built-in support for mSQL, DBM, and Postgres95 databases
User-defined functions
Cookie handling capabilities
Simple form processing
PHP/FI 2.0 (November 1997)
PHP/FI 2.0 introduced the revolutionary concept of embedding code directly within HTML documents, setting a precedent that would define PHP’s approach to web development:
Form handling capabilities
HTML embedding support
Improved database connectivity
Basic flow control structures
By 1997, PHP/FI had gained significant traction, with approximately 50,000 domains using the technology.
PHP 3.0 (June 1998)
PHP 3.0 marked a complete rewrite of the language, spearheaded by Andi Gutmans and Zeev Suraski, who would later found Zend Technologies. This version transformed PHP from a simple scripting tool into a legitimate programming language:
Key Features:
Zend Engine – The first iteration of PHP’s core execution engine
Object-oriented support – Limited but functional OOP capabilities
Superglobals – Introduction of $_GET, $_POST, $_SESSION, and other superglobal arrays
Web server abstraction layer – Improved compatibility across different server environments
Output buffering – Control over when content is sent to the browser
Object overloading support – Advanced OOP functionality
The PHP 5 Era: Language Maturity (2004–2018)
PHP 5.0 (July 2004)
PHP 5.0 represented the most significant language upgrade since PHP 3.0, introducing features that established PHP as a mature, enterprise-ready language:
Key Features:
Zend Engine II – Completely rewritten execution engine with improved memory management
PDO (PHP Data Objects) – Unified database access layer supporting multiple database systems
Improved object model – Real constructors, destructors, abstract classes, and interfaces
Exception handling – Try-catch blocks for error management
SimpleXML – Simplified XML parsing and manipulation
PHP 5.1 (November 2005)
This release focused on stability and refinement:
Over 400 bug fixes
Improved date/time handling with DateTimeZone class
Custom autoloading support via spl_autoload_register()
PDO is enabled by default
Significant performance improvements
PHP 5.2 (November 2006)
PHP 5.2 enhanced security and data handling capabilities:
JSON extension – Native JSON encoding and decoding
Input filtering extension – filter_var() for data validation and sanitization
json_validate() function – Validate JSON without parsing
Dynamic class constant fetch – $class::{$constName}
mb_str_pad() function – Multibyte-safe string padding
Read-only property cloning – Deep clone readonly properties
Granular DateTime exceptions – More specific error handling
array_sum() and array_product() improvements – Better type handling
New Randomizer methods – getBytesFromString(), getFloat(), nextFloat()
PHP 8.4 (November 2024)
PHP 8.4 introduced transformative OOP features:
Key Features:
Property hooks – Define custom get/set logic for properties without explicit methods:
class User {
public string $fullName {
get => $this->firstName . ' ' . $this->lastName;
set => [$this->firstName, $this->lastName] = explode(' ', $value);
}
}
Asymmetric visibility – Different read/write visibility: public private(set) string $name;
new without parentheses – $user = new User()->save();
PHP 8.3 – Up to 52% performance improvement in certain frameworks compared to PHP 8.1
Why Keeping PHP Updated Matters
Security Considerations
Running outdated PHP versions exposes applications to known vulnerabilities. Once a PHP version reaches EOL:
No security patches are released
Known exploits remain unpatched
Compliance requirements may be violated
Third-party libraries drop support
Performance Benefits
Each PHP version brings optimizations that translate to:
Faster page load times
Reduced server resource consumption
Lower hosting costs
Better user experience
Access to Modern Features
Staying current enables developers to use:
Latest language syntax improvements
Modern frameworks require newer PHP versions
Up-to-date Composer packages
Contemporary development practices
How to Check Your PHP Version
Determine your current PHP version using these methods:
Command Line:
php -v
PHP Script:
<?php
echo 'PHP Version: ' . phpversion();
// Or more detailed:
phpinfo();
?>
WordPress: Navigate to Tools > Site Health > Info > Server
Upgrading PHP: Best Practices
Before Upgrading
Review release notes – Check for breaking changes and deprecations
Test in staging – Never upgrade production first
Update dependencies – Ensure all packages support the new version
Run automated tests – Verify application functionality
Check framework compatibility – Confirm your framework supports the target version
During Upgrade
Backup everything – Database, files, and configurations
Use version control – Track all changes
Monitor error logs – Watch for deprecation warnings
Test critical paths – Verify core functionality works
After Upgrading
Monitor performance – Compare metrics before and after
Review error logs – Address any new warnings
Update .htaccess or server configs – If needed for new version
Document the upgrade – Record any issues and solutions
Conclusion
The journey of PHP, from a basic CGI scripting tool to a powerful, high-performance programming language, really showcases its incredible adaptability and the commitment of its community. With each new version, we’ve seen significant enhancements in performance, security, and the overall experience for developers.
PHP 8.x represents the most feature-rich and performant era of PHP development, with innovations like JIT compilation, property hooks, enums, and the pipe operator making PHP more expressive and efficient than ever. The language continues to evolve with annual releases that refine its capabilities while maintaining backward compatibility where possible.
Whether you’re building a small website or an enterprise application, PHP remains a powerful, reliable choice backed by decades of development and a thriving global community.
About the writer
Hassan Tahir wrote this article, drawing on his experience to clarify WordPress concepts and enhance developer understanding. Through his work, he aims to help both beginners and professionals refine their skills and tackle WordPress projects with greater confidence.