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To crack a PHP interview in 2026, you must master PHP 8+ features (attributes, enums, match, JIT), OOP concepts, arrays and string functions, sessions vs cookies, prepared statements, and security practices like preventing SQL injection and XSS. PHP still powers a massive share of the web — WordPress, Laravel applications, WooCommerce stores, and countless business systems. This guide covers 30+ real PHP interview questions with model answers for freshers and experienced developers, plus a salary table for India (2026), preparation tips, and FAQs.
Introduction: PHP Is Not Dead — It Pays Salaries
Every year someone declares “PHP is dead,” and every year PHP quietly powers a huge majority of all websites whose server language is known — including WordPress (which alone runs over 40% of the web), Wikipedia, and massive parts of Facebook’s legacy stack. In India’s job market, PHP remains one of the highest-volume skills: agencies, e-commerce companies, SaaS startups on Laravel, and enterprises maintaining business-critical systems hire PHP developers continuously.
Modern PHP is also a different language than its reputation. PHP 8.x brought JIT compilation, typed properties, enums, attributes, match expressions, and serious performance — making “PHP is slow and messy” answers instantly outdated in interviews. Interviewers in 2026 specifically test whether you know modern PHP or learned from decade-old tutorials.
Here is the typical PHP interview structure:
| Interview Stage | What Is Tested | Typical Duration |
| Round 1 – Screening / MCQ | Syntax, arrays, strings, output questions | 30–45 minutes |
| Round 2 – Core PHP | OOP, sessions, forms, file handling, PHP 8 features | 45–60 minutes |
| Round 3 – Database + Security | MySQL, prepared statements, injection, XSS, CSRF | 45–60 minutes |
| Round 4 – Framework / Practical | Laravel/WordPress task, REST API building | 60–90 minutes |
| HR Round | Communication, salary, culture fit | 20–30 minutes |
If your target role uses Laravel, pair this guide with our detailed Laravel Interview Questions post, revise database rounds with Basic SQL Interview Questions, and prepare the final round with HR Interview Questions for Freshers.
Basic PHP Interview Questions for Freshers (Q1–Q12)
Q1. What is PHP, and what are its main features?
Answer: PHP (a recursive acronym for “PHP: Hypertext Preprocessor”) is an open-source, server-side scripting language designed for web development, created by Rasmus Lerdorf in 1994 and now maintained by the PHP Foundation. Key features: it is interpreted and loosely typed (with optional strict typing in modern PHP), embeds directly into HTML, supports all major databases (MySQL, PostgreSQL, SQLite), runs on every platform, has a massive ecosystem (Composer, Laravel, Symfony, WordPress), and since PHP 8 includes a JIT compiler for performance. PHP code executes on the server and sends plain HTML to the browser — a fundamental point freshers must articulate clearly.
Q2. What is the difference between echo and print?
Answer: Both output data, but echo can take multiple comma-separated arguments, returns no value, and is marginally faster; print accepts only one argument and returns 1, so it can technically be used inside expressions. In practice, echo is the standard. A useful add-on: print_r() and var_dump() are for debugging — var_dump() shows types and lengths, making it the developer’s best friend.
Q3. How do variables and data types work in PHP?
Answer: Variables start with $ and are dynamically typed — type is decided at runtime from the assigned value. PHP supports scalar types (int, float, string, bool), compound types (array, object, callable, iterable), and special types (null, resource). Since PHP 7, you can enforce strict typing with declare(strict_types=1) and type-hint parameters, returns, and (since 7.4) class properties. Mentioning strict types signals you write modern, professional PHP.
Q4. What is the difference between ==, ===, and != in PHP?
Answer: == compares values after type juggling (“5” == 5 is true), while === compares value and type (“5” === 5 is false). Important PHP 8 update: string-to-number comparison became saner — 0 == “foo” is now false (it was true in PHP 7!). Best practice: always use === and !==. Knowing the PHP 8 comparison change is a strong modern-PHP signal.
Q5. Explain the types of arrays in PHP.
Answer: PHP has three array forms: indexed arrays (numeric keys: [10, 20, 30]), associative arrays (named keys: [‘name’ => ‘Asha’, ‘city’ => ‘Ahmedabad’]), and multidimensional arrays (arrays of arrays). Under the hood, all PHP arrays are ordered hash maps — one structure serving as list, dictionary, and queue. Must-know functions: count(), array_merge(), array_keys(), in_array(), array_map(), array_filter(), sort()/usort(). Array manipulation questions dominate PHP coding rounds.
Q6. What is the difference between GET and POST methods?
Answer:
| Feature | GET | POST |
| Data location | URL query string | Request body |
| Visibility | Visible in URL/history | Hidden from URL |
| Size limit | ~2KB (URL limits) | Effectively unlimited |
| Caching/bookmarks | Yes | No |
| Use case | Search, filters, reads | Forms, logins, writes |
Access them via $_GET and $_POST superglobals. Security note that earns points: neither is “secure” by itself — sensitive data needs HTTPS, and all input needs validation regardless of method.
Q7. What are superglobals in PHP?
Answer: Superglobals are built-in variables accessible from any scope: $_GET, $_POST, $_REQUEST (combined input — avoid in serious code), $_SESSION (server-side user data), $_COOKIE (client-side data), $_FILES (uploads), $_SERVER (headers, paths, IPs), $_ENV (environment), and $GLOBALS. Interviewers commonly follow up with: “Why avoid $_REQUEST?” — because it mixes sources, creating ambiguity and potential security issues.
Q8. What is the difference between sessions and cookies?
Answer: A cookie is a small piece of data stored in the user’s browser and sent with every request — set via setcookie(), readable by the client, limited to ~4KB. A session stores data on the server, with only a session ID cookie (PHPSESSID) on the client — started with session_start(), accessed via $_SESSION, more secure for sensitive data like login state. Classic follow-ups: “Where do sessions live?” (server files/Redis/database), “What happens if cookies are disabled?” (session ID via URL — discouraged), and “How do you destroy a session?” (session_destroy() plus unsetting the cookie).
Q9. What is the difference between include, require, include_once, and require_once?
Answer: All four pull external files into a script. include emits a warning and continues if the file is missing; require throws a fatal error and stops — use require for essential files like configs. The _once variants prevent the same file from loading twice, avoiding function redefinition errors. In modern PHP, Composer’s PSR-4 autoloading has largely replaced manual includes for classes — mentioning autoloading shows real-world experience.
Q10. How does form handling work in PHP?
Answer: The HTML form’s action points to a PHP script and method chooses GET/POST. PHP reads input from the superglobals, then — critically — validates and sanitizes everything: filter_var($email, FILTER_VALIDATE_EMAIL) for validation, htmlspecialchars() before output to prevent XSS, prepared statements before database use to prevent SQL injection. The golden interview line: “Never trust user input — validate on arrival, escape on output.”
Q11. What are PHP string functions you use most?
Answer: Core ones every interview touches: strlen() (length), str_replace() (replace), substr() (slice), strpos() (find position), strtolower()/strtoupper(), trim() (strip whitespace), explode() (string → array), implode() (array → string), sprintf() (formatting), and PHP 8’s clean trio str_contains(), str_starts_with(), str_ends_with(). Using str_contains() instead of the old strpos() !== false idiom instantly marks you as a modern PHP developer.
Q12. What is the difference between unset() and unlink()?
Answer: unset() destroys a variable (removes it from memory/scope), while unlink() deletes a file from the filesystem. A classic one-liner trap question. Related pair: empty() checks if a variable is empty/falsy without warning, isset() checks if it exists and is not null — and isset() returns false for null values, which surprises many freshers.
Intermediate PHP Interview Questions (Q13–Q22)
Q13. Explain OOP concepts in PHP.
Answer: PHP supports full object-oriented programming: classes/objects, encapsulation (public/protected/private visibility), inheritance (extends, single inheritance only), polymorphism (method overriding; “overloading” in PHP means magic methods, not signature overloading — a famous trap), and abstraction (abstract classes and interfaces). Modern additions to mention: constructor property promotion (PHP 8), readonly properties (8.1), enums (8.1), and first-class callable syntax. OOP questions fill at least a third of any PHP interview.
Q14. What is the difference between an abstract class and an interface?
Answer:
| Feature | Abstract Class | Interface |
| Methods | Mix of implemented + abstract | Declarations only (no body) |
| Properties | Yes | Constants only |
| Inheritance | One abstract class | Implement many interfaces |
| Constructor | Can have one | Cannot |
| Use case | Shared base behavior | Contract/capability |
Rule of thumb for the interview: “Abstract class = what something is; interface = what something can do.” Since PHP 8, you can combine interfaces with traits for reusable implementation — mentioning traits (PHP’s answer to multiple inheritance) strengthens the answer.
Q15. What are traits in PHP?
Answer: Traits are reusable blocks of methods that can be “mixed into” multiple classes with use TraitName;, solving single inheritance limitations. Example: a Loggable trait providing log() to both Order and Invoice classes that extend different parents. Conflict resolution uses insteadof and as operators. Laravel uses traits heavily (SoftDeletes, Notifiable), so framework-bound interviews love this question.
Q16. What are magic methods in PHP?
Answer: Magic methods start with __ and trigger automatically: __construct()/__destruct() (lifecycle), __get()/__set() (inaccessible property access), __call()/__callStatic() (inaccessible method calls — how Laravel facades work), __toString() (object → string), __invoke() (calling object as function), and __clone() (copy behavior). Explaining that Eloquent’s fluent magic is built on __call() connects theory to the real world — interview gold.
Q17. What new features did PHP 8.x introduce?
Answer: The modern-PHP checklist: JIT compiler (performance), named arguments (createUser(name: ‘Asha’, active: true)), constructor property promotion, union types (int|string) and nullable types, match expression (strict, value-returning switch), nullsafe operator ($user?->address?->city), attributes (native annotations #[Route(‘/home’)]), enums (8.1), readonly properties/classes, fibers (8.1, async foundations), and never return type. Listing 5–6 of these fluently is often the deciding question between candidates in 2026.
Q18. How do you connect PHP to MySQL, and what are prepared statements?
Answer: Two modern options: MySQLi (MySQL-only) and PDO (database-agnostic — preferred). The old mysql_* functions are removed; mentioning them as current fails interviews. Prepared statements separate SQL structure from data: the query template is sent first (SELECT * FROM users WHERE email = ?), then values are bound — making SQL injection structurally impossible while also improving repeated-query performance. Writing a PDO prepared statement from memory is a standard coding-round task; practice it.
Q19. How do you prevent SQL injection, XSS, and CSRF in PHP?
Answer: The security trio every PHP interview includes. SQL injection: prepared statements with PDO/MySQLi, never string-concatenated queries. XSS: escape all output with htmlspecialchars($data, ENT_QUOTES, ‘UTF-8’), set Content-Security-Policy headers. CSRF: generate a random token per session, embed it in forms, verify on submission (frameworks automate this). Bonus protections: password_hash()/password_verify() for passwords (never md5/sha1!), httpOnly + secure + SameSite cookie flags, and HTTPS everywhere. Security answers separate hireable developers from hobbyists.
Q20. What is the difference between require and Composer autoloading?
Answer: Manual require statements force you to track every file dependency yourself. Composer, PHP’s dependency manager, generates a PSR-4 autoloader: you map namespaces to directories in composer.json, include one file (vendor/autoload.php), and classes load automatically on first use. Composer also manages third-party packages from Packagist with semantic versioning via composer.lock. Modern PHP development is unthinkable without Composer — describe your workflow with it confidently.
Q21. Explain error handling in PHP.
Answer: Modern PHP uses exceptions: try { } catch (SpecificException $e) { } finally { }, with custom exceptions extending Exception. Since PHP 7, most fatal errors became Error objects — both Error and Exception implement Throwable, so catch (Throwable $t) is the universal net. Configuration matters: display_errors=On in development, Off in production with log_errors=On. Mentioning structured logging (Monolog) and the difference between errors, warnings, and notices completes a senior-sounding answer.
Q22. What is the difference between == null, is_null(), and isset()?
Answer: is_null($x) and $x === null are equivalent strict checks. isset($x) returns true only if the variable exists and is not null — it never throws on undefined variables, making it the safe existence check. empty($x) is looser: true for null, 0, ““,”0”, false, and empty arrays. Trap question: isset($arr[‘key’]) returns false if the value is null even when the key exists — array_key_exists() is the precise check. These nuance questions are PHP interview favorites.
Advanced & Scenario-Based PHP Interview Questions (Q23–Q30)
Q23. How does PHP handle a request under the hood (request lifecycle)?
Answer: Browser sends a request → web server (Nginx/Apache) routes it to PHP via PHP-FPM (FastCGI Process Manager) → PHP parses the script to opcodes (cached by OPcache so parsing happens once) → executes, queries databases, builds output → returns the response, and the process resets (PHP’s shared-nothing architecture: each request starts clean). Explaining OPcache and PHP-FPM tuning (pm.max_children) demonstrates deployment experience that most candidates lack.
Q24. What are generators in PHP, and when would you use them?
Answer: Generators use yield to produce values lazily one at a time instead of building entire arrays in memory. Iterating a 2-GB CSV: a generator reads line by line in constant memory, while an array approach crashes. They implement Iterator automatically and support yield from for delegation. Real scenario answer: “I used a generator to export 1 million database rows to CSV in chunks without exhausting memory” — concrete examples like this win interviews.
Q25. Scenario: A PHP page is loading slowly. How do you find and fix the problem?
Answer: Diagnose first: enable slow query logging, profile with Xdebug/Blackfire, check server logs. Common culprits and fixes: N+1 database queries (use joins/eager loading), missing indexes (EXPLAIN the queries), no OPcache (enable it — instant major speedup), heavy loops over large arrays (generators, chunking), no caching layer (add Redis/Memcached for sessions and hot data), external API calls in request path (queue them). Close with: “I measure before and after every change — optimization without measurement is guessing.”
Q26. How do sessions scale across multiple servers?
Answer: Default file-based sessions break behind load balancers (user hits server B, session file lives on server A). Solutions: centralized session storage in Redis or Memcached (session.save_handler = redis), database-backed sessions, or sticky sessions at the load balancer (simpler but limits flexibility). For APIs, stateless JWT tokens remove server-side sessions entirely. This question tests whether you have deployed PHP beyond localhost.
Q27. What is the difference between PHP-FPM and mod_php? What about new runtimes?
Answer: mod_php embeds PHP inside Apache — simple but every Apache process carries PHP’s memory weight. PHP-FPM runs PHP as a separate FastCGI process pool — works with Nginx, isolates resources, and is the production standard. The 2026 frontier: long-running application servers like Swoole, RoadRunner, and FrankenPHP keep the app booted in memory between requests, delivering dramatic speedups (Laravel Octane uses these). Naming these modern runtimes is a strong differentiator.
Q28. Scenario: How would you build a simple REST API in plain PHP?
Answer: Outline the structure: a front controller (index.php) receiving all requests via web-server rewrite rules; read method from $_SERVER[‘REQUEST_METHOD’] and path from parse_url(); route to handlers (GET /products → list, POST /products → create); read JSON body with json_decode(file_get_contents(‘php://input’), true); respond with header(‘Content-Type: application/json’), proper status codes (http_response_code(201)), and json_encode(); secure with token authentication, input validation, and prepared statements. Then add: “In production I’d use Laravel or Slim for routing, middleware, and validation out of the box.”
Q29. How do you test PHP code?
Answer: PHPUnit is the standard: unit tests for pure logic, test doubles (mocks/stubs) for dependencies, data providers for input matrices, and assertions (assertSame, assertEquals). Pest is the modern, expressive layer over PHPUnit gaining huge adoption. Complement with static analysis — PHPStan or Psalm catch type bugs without running code — and code style via PHP-CS-Fixer. Describing a CI pipeline (tests + static analysis on every push) elevates your answer to senior level.
Q30. WordPress vs Laravel — when would you choose each?
Answer: WordPress: content-driven sites, blogs, marketing sites, quick e-commerce via WooCommerce — fast delivery, huge plugin ecosystem, non-technical admin editing. Laravel: custom applications — SaaS products, APIs, dashboards, complex business logic — with elegant ORM (Eloquent), queues, testing, and modern architecture. The mature answer: “I choose based on the problem: content site in days → WordPress; custom product with complex logic → Laravel.” For deep framework rounds, study our complete Laravel Interview Questions guide.
PHP Developer Salary in India (2026)
| Experience Level | Role | Average Salary (per annum) |
| 0–2 years (Fresher) | Junior PHP Developer | ₹2.5 – ₹4.5 LPA |
| 2–5 years | PHP / Laravel Developer | ₹5 – ₹10 LPA |
| 5–8 years | Senior PHP Developer | ₹10 – ₹18 LPA |
| 8+ years | Tech Lead / Architect | ₹18 – ₹32+ LPA |
Laravel expertise commands a clear premium over core-PHP-only profiles, and PHP + Vue/React full-stack combinations push offers higher still.
7 Proven Tips to Crack Your PHP Interview
- Speak modern PHP — PHP 8 features, strict types, Composer, PSR standards. Outdated mysql_* era answers are instant rejections.
- Drill the security trio — SQL injection, XSS, CSRF with concrete prevention code. Every PHP interview tests security.
- Practice array and string challenges — reverse a string without functions, find duplicates in an array, flatten nested arrays. These dominate coding rounds.
- Write prepared statements from memory — PDO connection + prepared insert/select is the most common live-coding task.
- Know one framework deeply — Laravel preferred; explain routing, middleware, Eloquent, and migrations confidently.
- Understand deployment basics — PHP-FPM, OPcache, environment configs. It distinguishes professionals from tutorial learners.
- Prepare a project walkthrough — schema design, security measures, one performance problem you solved with numbers.
Recommended Resources to Prepare Faster
| Resource | Type | Best For | Link |
| PHP & MySQL: Novice to Ninja | Book | Complete foundation | [Affiliate Link] |
| Laracasts (PHP + Laravel paths) | Video Platform | Modern PHP mastery | [Affiliate Link] |
| PHP 8 Objects, Patterns, and Practice | Book | OOP + design patterns | [Affiliate Link] |
| Modern PHP Bootcamp | Online Course | Interview-focused prep | [Affiliate Link] |
| PHPStan / Testing Masterclass | Course | Senior-level skills | [Affiliate Link] |
Affiliate Disclosure: Some links in this section are affiliate links. If you purchase through them, we may earn a small commission at no extra cost to you. We only recommend resources we genuinely believe will help your interview preparation.
Always verify language behavior in the official PHP documentation — interviewers respect candidates who cite php.net.
FAQ: PHP Interview Questions
Q1. Is PHP worth learning in 2026?
Yes. PHP powers a dominant share of the web, job volume in India remains among the highest of any back-end language, and modern PHP 8 + Laravel is a genuinely pleasant, productive stack with strong salaries at the senior level.
Q2. What is the most asked PHP interview question?
“Difference between sessions and cookies” tops fresher interviews, followed by GET vs POST, include vs require, and == vs ===. For experienced roles, security prevention and PHP 8 features lead.
Q3. Do I need to know Laravel for PHP interviews?
For most modern PHP jobs, yes — Laravel appears in the majority of Indian PHP job descriptions. Core PHP gets you through fundamentals rounds, but framework fluency gets you the offer.
Q4. How long does it take to prepare for a PHP interview?
With basic programming knowledge: 3–4 weeks. Week 1 core PHP + arrays/strings, week 2 OOP + PHP 8 features, week 3 MySQL + security, week 4 Laravel basics + mock interviews.
Q5. PHP vs Node.js — which is better for backend jobs?
Both have strong markets. PHP offers more job volume (WordPress/Laravel ecosystems) especially in agencies and SMEs; Node.js trends in startups and real-time apps. Salaries converge at senior levels — choose based on target companies. Compare with our Node.js Interview Questions guide.
Conclusion
PHP interviews in 2026 reward developers who know the modern language: PHP 8 features, security-first habits, Composer-based workflows, and framework fluency. Work through all 30 questions, write the code yourself — especially prepared statements and OOP structures — and pair this guide with our Laravel and SQL guides for complete preparation. The PHP job market is large, active, and pays well for skilled developers; walk in prepared and claim your offer.
Bookmark this page, share it with fellow developers, and explore our other interview guides for every round of your journey.
Disclaimer: This article is for educational purposes only. Interview questions, salary figures, and hiring trends mentioned here are indicative and may vary by company, location, and market conditions. Always research the specific company and role you are applying for.