Below is a carefully curated list of the top 75 PHP interview questions and answers, written in simple English, practical, and interview-focused. These questions are commonly asked in freshers, experienced, technical, and HR rounds.
Table of Contents:
75 Powerful PHP Interview Questions and Answers 2025–26 for Guaranteed Success
PHP remains one of the most in-demand backend programming languages in 2025–26, powering millions of websites and applications. Whether you are a student, fresher, or experienced PHP developer, preparing with the right interview questions can significantly boost your success rate.
This page provides complete, updated, and practical PHP interview questions and answers designed for real interviews, written in simple English with examples and output for easy understanding.
Why PHP Interview Questions Are Still Important in 2025–26
PHP continues to dominate server-side development because of:
- Strong support for MySQL and databases
- Popular frameworks like Laravel and CodeIgniter
- High demand in freelancing and startups
- Easy learning curve with powerful features
If you are learning PHP, we recommend starting with our basic to advanced PHP tutorials on
👉 https://www.phponline.in/php-tutorial
Basic PHP Interview Questions and Answers for Freshers
What is PHP and why is it used?
PHP (Hypertext Preprocessor) is an open-source server-side scripting language used to create dynamic web applications.
Key Uses of PHP:
- Server-side scripting
- Form handling
- Database interaction
- Session management
How does PHP work?
PHP code runs on the server, and the output is sent to the browser as HTML.
Example:
<?php
echo "Welcome to PHP Online";
?>
Output:
Welcome to PHP Online75 Powerful PHP Interview Questions and Answers 2025–26
Question 1: What is PHP?
Answer: PHP stands for Hypertext Preprocessor. It is an open-source server-side scripting language used to develop dynamic and interactive web applications. PHP code is executed on the server and the result is returned to the browser as HTML.
Question 2: Why is PHP used?
Answer: PHP is used because it is easy to learn, open source, platform independent, supports databases, and is widely used in real-world web applications like WordPress, Laravel, and e-commerce platforms.
Question 3: What are the main features of PHP?
Answer: PHP features include open source availability, fast execution, cross-platform support, database integration, built-in security functions, and strong community support.
Question 4: What are the latest PHP versions used in 2025–26?
Answer: PHP 8 and later versions are widely used in 2025–26. They offer better performance, improved error handling, JIT compilation, and modern language features.
Question 5: What is the difference between PHP and JavaScript?
Answer: PHP is a server-side language executed on the server, while JavaScript is primarily a client-side language executed in the browser. PHP handles backend logic, while JavaScript handles frontend interactions.
Question 6: How does PHP work?
Answer: When a user requests a PHP page, the server processes the PHP code, generates HTML output, and sends it to the browser. The browser never sees the PHP source code.
Question 7: What is a variable in PHP?
Answer: A variable is used to store data. In PHP, variables start with a dollar sign followed by the variable name.
Example:
Output:
PHP Online
Question 8: What are PHP data types?
Answer: PHP supports string, integer, float, boolean, array, object, null, and resource data types.
Question 9: What is the difference between echo and print?
Answer: echo can output multiple values and is faster, while print returns a value and can output only one string.
Question 10: What are constants in PHP?
Answer: Constants are identifiers whose values cannot be changed once defined. They are defined using define() or const.
Question 11: What are PHP operators?
Answer: PHP operators are symbols used to perform operations such as arithmetic, comparison, logical, assignment, and increment/decrement operations.
Question 12: What is an array in PHP?
Answer: An array is a variable that stores multiple values.
Question 13: What are the types of arrays in PHP?
Answer: Indexed arrays, associative arrays, and multidimensional arrays.
Question 14: What is foreach loop?
Answer: foreach is used to iterate over arrays.
Question 15: What is a function in PHP?
Answer: A function is a reusable block of code that performs a specific task.
Question 16: What is function parameter passing?
Answer: Parameters can be passed by value or by reference using the ampersand symbol.
Question 17: What is variable scope?
Answer: Variable scope defines where a variable can be accessed. PHP supports local, global, and static scope.
Question 18: What are superglobals in PHP?
Answer: Superglobals are predefined variables like $_GET, $_POST, $_SESSION, $_COOKIE, $_SERVER, and $_FILES.
Question 19: What is $_GET?
Answer: $_GET is used to collect data sent through URL parameters.
Question 20: What is $_POST?
Answer: $_POST is used to collect data sent through HTML forms securely.
Question 21: What is session in PHP?
Answer: A session stores user data on the server across multiple pages.
Question 22: What is a cookie?
Answer: A cookie stores data on the user’s browser for a specific time.
Question 23: Difference between session and cookie?
Answer: Sessions are stored on the server and are more secure, while cookies are stored on the client.
Question 24: What is file handling in PHP?
Answer: PHP can read, write, upload, and delete files using built-in functions.
Question 25: What is include and require?
Answer: Both include files. require causes a fatal error if file not found, include gives a warning.
Question 26: What is OOP in PHP?
Answer: Object-Oriented Programming is a programming style based on classes and objects.
Question 27: What is a class?
Answer: A class is a blueprint for creating objects.
Question 28: What is an object?
Answer: An object is an instance of a class.
Question 29: What is inheritance?
Answer: Inheritance allows one class to acquire properties of another class.
Question 30: What is encapsulation?
Answer: Encapsulation protects data by restricting access using access modifiers.
Question 31: What is polymorphism?
Answer: Polymorphism allows methods to have different behaviors.
Question 32: What are access modifiers?
Answer: public, private, and protected.
Question 33: What is an interface?
Answer: An interface defines methods that a class must implement.
Question 34: What is a trait?
Answer: Traits allow code reuse in PHP.
Question 35: What is namespace?
Answer: Namespaces prevent class name conflicts.
Question 36: What is MySQL?
Answer: MySQL is a relational database management system.
Question 37: How to connect PHP with MySQL?
Answer: Using MySQLi or PDO.
Question 38: What is PDO?
Answer: PDO is a database access layer that supports multiple databases.
Question 39: What is SQL Injection?
Answer: SQL Injection is a security attack where malicious SQL code is injected.
Question 40: How to prevent SQL Injection?
Answer: Using prepared statements and input validation.
Question 41: What is password hashing?
Answer: Password hashing converts passwords into secure hashes.
Question 42: Which function is used for hashing passwords?
Answer: password_hash().
Question 43: What is password_verify()?
Answer: It verifies a password against a hash.
Question 44: What is error handling in PHP?
Answer: Error handling manages runtime errors using error reporting and exceptions.
Question 45: What is try-catch?
Answer: try-catch handles exceptions in PHP.
Question 46: What is REST API?
Answer: REST API allows communication between applications using HTTP methods.
Question 47: What is JSON?
Answer: JSON is a lightweight data-interchange format.
Question 48: What is composer?
Answer: Composer is a dependency manager for PHP.
Question 49: What is MVC?
Answer: MVC stands for Model View Controller architecture.
Question 50: What is Laravel?
Answer: Laravel is a popular PHP framework.
Question 51: What is routing?
Answer: Routing maps URLs to controllers.
Question 52: What is middleware?
Answer: Middleware filters HTTP requests.
Question 53: What is CSRF?
Answer: Cross-Site Request Forgery attack.
Question 54: How to prevent CSRF?
Answer: Using CSRF tokens.
Question 55: What is XSS?
Answer: Cross-Site Scripting attack.
Question 56: How to prevent XSS?
Answer: Escaping output and validating input.
Question 57: What is caching?
Answer: Caching improves performance by storing frequently used data.
Question 58: What is opcode cache?
Answer: It stores compiled PHP code in memory.
Question 59: What is cron job?
Answer: A scheduled task executed automatically.
Question 60: What is file upload validation?
Answer: It checks file type, size, and security.
Question 61: What is MVC advantage?
Answer: Better code organization and maintainability.
Question 62: What is API authentication?
Answer: Securing APIs using tokens or keys.
Question 63: What is JWT?
Answer: JSON Web Token for authentication.
Question 64: What is dependency injection?
Answer: Passing dependencies instead of creating them.
Question 65: What is late static binding?
Answer: It refers to static method resolution at runtime.
Question 66: What is magic method?
Answer: Special methods starting with __ like __construct.
Question 67: What is autoloading?
Answer: Automatically loading classes when needed.
Question 68: What is SPL?
Answer: Standard PHP Library.
Question 69: What is unit testing?
Answer: Testing individual components.
Question 70: What is PHPUnit?
Answer: A testing framework for PHP.
Question 71: What is scalability?
Answer: Ability to handle increased load.
Question 72: What is load balancing?
Answer: Distributing traffic across servers.
Question 73: What is cloud hosting?
Answer: Hosting applications on cloud infrastructure.
Question 74: Is PHP good for freelancing?
Answer: Yes, PHP has high freelancing demand.
Question 75: Is PHP still relevant in 2025–26?
Answer: Yes, PHP remains highly relevant due to massive existing systems and modern frameworks.
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