How to Create a Simple Login System in PHP

A login system is one of the most essential features of any website or web application. Whether it’s an e-commerce site, a blogging platform, or an internal company portal, user authentication ensures that only authorized users can access specific areas. In this article, we’ll walk through creating a simple login system in PHP using MySQL.

Prerequisites

Before you start, make sure you have:

A local server environment (XAMPP, WAMP, or MAMP).

Basic knowledge of PHP and MySQL.

A database created with a users table.

Step 1: Create the Database

First, create a database named login_system and a users table.

CREATE DATABASE login_system;

USE login_system;

CREATE TABLE users (
id INT AUTO_INCREMENT PRIMARY KEY,
username VARCHAR(50) NOT NULL,
email VARCHAR(100) NOT NULL,
password VARCHAR(255) NOT NULL
);

You can manually insert a user with an encrypted password:

INSERT INTO users (username, email, password)
VALUES ('testuser', 'test@example.com', MD5('12345'));

Step 2: Database Connection (db.php)

<?php
$host = "localhost";
$user = "root";
$pass = "";
$dbname = "login_system";

$conn = new mysqli($host, $user, $pass, $dbname);

if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
?>

Step 3: Create Login Form (login.php)

<!DOCTYPE html>
<html>
<head>
<title>Login System in PHP</title>
</head>
<body>
<h2>Login</h2>
<form action="login_process.php" method="POST">
<label>Username:</label><br>
<input type="text" name="username" required><br><br>

<label>Password:</label><br>
<input type="password" name="password" required><br><br>

<input type="submit" value="Login">
</form>
</body>
</html>

Step 4: Process Login (login_process.php)

<?php
session_start();
include 'db.php';

$username = $_POST['username'];
$password = md5($_POST['password']);

$sql = "SELECT * FROM users WHERE username='$username' AND password='$password'";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
$_SESSION['username'] = $username;
header("Location: dashboard.php");
exit();
} else {
echo "Invalid Username or Password!";
}
?>

Step 5: Create Dashboard (dashboard.php)

<?php
session_start();
if (!isset($_SESSION['username'])) {
header("Location: login.php");
exit();
}
?>

<!DOCTYPE html>
<html>
<head>
<title>Dashboard</title>
</head>
<body>
<h2>Welcome, <?php echo $_SESSION['username']; ?>!</h2>
<a href="logout.php">Logout</a>
</body>
</html>

Step 6: Logout (logout.php)

<?php
session_start();
session_unset();
session_destroy();
header("Location: login.php");
exit();
?>

Step 7: Secure the System

Use password_hash() and password_verify() instead of MD5 for better security.

Validate and sanitize user input.

Implement CSRF protection for advanced security.

Download PHP login system with dashboard