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Base URL and Index page settings

Last modified on: September 9, 2025

<h1 data-start="457" data-end="511">📝 Base URL and Index Page Settings in CodeIgniter</h1>
<h2 data-start="513" data-end="559">🔎 Why Configure Base URL and Index Page?</h2>
<ul data-start="560" data-end="692">
<li data-start="560" data-end="619">
<p data-start="562" data-end="619"><strong data-start="562" data-end="574">Base URL</strong>: Defines the root URL of your application.</p>
</li>
<li data-start="620" data-end="692">
<p data-start="622" data-end="692"><strong data-start="622" data-end="636">Index Page</strong>: Determines whether <code data-start="657" data-end="668">index.php</code> appears in your URLs.</p>
</li>
</ul>
<p data-start="694" data-end="726">👉 Example:<br data-start="705" data-end="708" />Without config &rarr;</p>
<div class="contain-inline-size rounded-2xl relative bg-token-sidebar-surface-primary">
<div class="sticky top-9">
<div class="absolute end-0 bottom-0 flex h-9 items-center pe-2">
<div class="bg-token-bg-elevated-secondary text-token-text-secondary flex items-center gap-4 rounded-sm px-2 font-sans text-xs">
<pre class="language-php"><code>http://localhost/ci/index.php/home
</code></pre>
</div>
</div>
</div>
</div>
<p data-start="772" data-end="794">With proper config &rarr;</p>
<div class="contain-inline-size rounded-2xl relative bg-token-sidebar-surface-primary">
<div class="sticky top-9">
<div class="absolute end-0 bottom-0 flex h-9 items-center pe-2">
<div class="bg-token-bg-elevated-secondary text-token-text-secondary flex items-center gap-4 rounded-sm px-2 font-sans text-xs">
<pre class="language-php"><code>http://localhost/ci/home
</code></pre>
</div>
</div>
</div>
</div>
<p data-start="831" data-end="889">This improves <strong data-start="845" data-end="886">SEO, readability, and user experience</strong>.</p>
<hr data-start="891" data-end="894" />
<h2 data-start="896" data-end="945">📂 1. Base URL &amp; Index Page in CodeIgniter 3</h2>
<h3 data-start="947" data-end="997">Step 1: Open <code data-start="964" data-end="995">application/config/config.php</code></h3>
<h4 data-start="999" data-end="1021">🔹 Set Base URL</h4>
<div class="contain-inline-size rounded-2xl relative bg-token-sidebar-surface-primary">
<div class="sticky top-9">
<div class="absolute end-0 bottom-0 flex h-9 items-center pe-2">
<div class="bg-token-bg-elevated-secondary text-token-text-secondary flex items-center gap-4 rounded-sm px-2 font-sans text-xs">
<pre class="language-php"><code>$config['base_url'] = 'http://localhost/ci/';
</code></pre>
</div>
</div>
</div>
</div>
<p data-start="1079" data-end="1145">👉 Change <code data-start="1089" data-end="1104">localhost/ci/</code> to your project folder or domain name.</p>
<h4 data-start="1147" data-end="1171">🔹 Set Index Page</h4>
<div class="contain-inline-size rounded-2xl relative bg-token-sidebar-surface-primary">
<div class="sticky top-9">
<div class="absolute end-0 bottom-0 flex h-9 items-center pe-2">
<div class="bg-token-bg-elevated-secondary text-token-text-secondary flex items-center gap-4 rounded-sm px-2 font-sans text-xs">
<pre class="language-php"><code>$config['index_page'] = '';
</code></pre>
</div>
</div>
</div>
</div>
<p data-start="1211" data-end="1260">👉 Leave empty to remove <code data-start="1236" data-end="1247">index.php</code> from URLs.</p>
<h3 data-start="1262" data-end="1321">Step 2: Configure <code data-start="1284" data-end="1295">.htaccess</code> (to remove <code data-start="1307" data-end="1318">index.php</code>)</h3>
<p data-start="1322" data-end="1369">Create a <code data-start="1331" data-end="1342">.htaccess</code> file in the root folder:</p>
<div class="contain-inline-size rounded-2xl relative bg-token-sidebar-surface-primary">
<div class="sticky top-9">
<div class="absolute end-0 bottom-0 flex h-9 items-center pe-2">
<div class="bg-token-bg-elevated-secondary text-token-text-secondary flex items-center gap-4 rounded-sm px-2 font-sans text-xs">
<pre class="language-php"><code>&lt;IfModule mod_rewrite.c&gt;
    RewriteEngine On
    RewriteBase /ci/

# Remove index.php from URL
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteRule ^(.*)$ index.php/$1 [L]
&lt;/IfModule&gt;
</code></pre>
</div>
</div>
</div>
</div>
<p data-start="1617" data-end="1647">👉 Now your URLs look clean:</p>
<div class="contain-inline-size rounded-2xl relative bg-token-sidebar-surface-primary">
<div class="sticky top-9">
<div class="absolute end-0 bottom-0 flex h-9 items-center pe-2">
<div class="bg-token-bg-elevated-secondary text-token-text-secondary flex items-center gap-4 rounded-sm px-2 font-sans text-xs">
<pre class="language-php"><code>http://localhost/ci/home
</code></pre>
</div>
</div>
</div>
</div>
<hr data-start="1682" data-end="1685" />
<h2 data-start="1687" data-end="1736">📂 2. Base URL &amp; Index Page in CodeIgniter 4</h2>
<h3 data-start="1738" data-end="1777">Step 1: Open <code data-start="1755" data-end="1775">app/Config/App.php</code></h3>
<h4 data-start="1779" data-end="1801">🔹 Set Base URL</h4>
<div class="contain-inline-size rounded-2xl relative bg-token-sidebar-surface-primary">
<div class="sticky top-9">
<div class="absolute end-0 bottom-0 flex h-9 items-center pe-2">
<div class="bg-token-bg-elevated-secondary text-token-text-secondary flex items-center gap-4 rounded-sm px-2 font-sans text-xs">
<pre class="language-php"><code>public $baseURL = 'http://localhost:8080/';
</code></pre>
</div>
</div>
</div>
</div>
<p data-start="1857" data-end="1896">👉 Use your domain or localhost port.</p>
<h4 data-start="1898" data-end="1922">🔹 Set Index Page</h4>
<div class="contain-inline-size rounded-2xl relative bg-token-sidebar-surface-primary">
<div class="sticky top-9">
<div class="absolute end-0 bottom-0 flex h-9 items-center pe-2">
<div class="bg-token-bg-elevated-secondary text-token-text-secondary flex items-center gap-4 rounded-sm px-2 font-sans text-xs">
<pre class="language-php"><code>public $indexPage = '';
</code></pre>
</div>
</div>
</div>
</div>
<p data-start="1958" data-end="2005">👉 Set empty to remove <code data-start="1981" data-end="1992">index.php</code> from URLs.</p>
<h3 data-start="2007" data-end="2066">Step 2: Configure <code data-start="2029" data-end="2040">.htaccess</code> (to remove <code data-start="2052" data-end="2063">index.php</code>)</h3>
<p data-start="2067" data-end="2122">Create/edit <code data-start="2079" data-end="2090">.htaccess</code> inside the <strong data-start="2102" data-end="2112">public</strong> folder:</p>
<div class="contain-inline-size rounded-2xl relative bg-token-sidebar-surface-primary">
<div class="sticky top-9">
<div class="absolute end-0 bottom-0 flex h-9 items-center pe-2">
<div class="bg-token-bg-elevated-secondary text-token-text-secondary flex items-center gap-4 rounded-sm px-2 font-sans text-xs">
<pre class="language-php"><code>&lt;IfModule mod_rewrite.c&gt;
    Options -Indexes
    RewriteEngine On
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteRule ^(.*)$ index.php/$1 [L]
&lt;/IfModule&gt;
</code></pre>
</div>
</div>
</div>
</div>
<p data-start="2337" data-end="2359">👉 Your URLs become:</p>
<div class="contain-inline-size rounded-2xl relative bg-token-sidebar-surface-primary">
<div class="sticky top-9">
<div class="absolute end-0 bottom-0 flex h-9 items-center pe-2">
<div class="bg-token-bg-elevated-secondary text-token-text-secondary flex items-center gap-4 rounded-sm px-2 font-sans text-xs">
<pre class="language-php"><code>http://localhost:8080/home
</code></pre>
</div>
</div>
</div>
</div>
<hr data-start="2396" data-end="2399" />
<h2 data-start="2401" data-end="2441">📊 CI3 vs CI4 Base URL &amp; Index Page</h2>
<div class="_tableContainer_1rjym_1">
<div class="_tableWrapper_1rjym_13 group flex w-fit flex-col-reverse" tabindex="-1">
<table class="w-fit min-w-(--thread-content-width)" data-start="2443" data-end="3042">
<thead data-start="2443" data-end="2542">
<tr data-start="2443" data-end="2542">
<th data-start="2443" data-end="2461" data-col-size="sm">Feature</th>
<th data-start="2461" data-end="2500" data-col-size="sm">CodeIgniter 3</th>
<th data-start="2500" data-end="2542" data-col-size="sm">CodeIgniter 4</th>
</tr>
</thead>
<tbody data-start="2643" data-end="3042">
<tr data-start="2643" data-end="2742">
<td data-start="2643" data-end="2661" data-col-size="sm">Base URL Config</td>
<td data-start="2661" data-end="2700" data-col-size="sm"><code data-start="2663" data-end="2684">$config['base_url']</code> in <code data-start="2688" data-end="2700">config.php</code></td>
<td data-start="2700" data-end="2742" data-col-size="sm"><code data-start="2702" data-end="2712">$baseURL</code> in <code data-start="2716" data-end="2725">App.php</code></td>
</tr>
<tr data-start="2743" data-end="2842">
<td data-start="2743" data-end="2761" data-col-size="sm">Index Page</td>
<td data-start="2761" data-end="2800" data-col-size="sm"><code data-start="2763" data-end="2786">$config['index_page']</code></td>
<td data-start="2800" data-end="2842" data-col-size="sm"><code data-start="2802" data-end="2814">$indexPage</code></td>
</tr>
<tr data-start="2843" data-end="2942">
<td data-start="2843" data-end="2861" data-col-size="sm">Remove Index</td>
<td data-start="2861" data-end="2900" data-col-size="sm"><code data-start="2863" data-end="2874">.htaccess</code> rewrite</td>
<td data-start="2900" data-end="2942" data-col-size="sm"><code data-start="2902" data-end="2913">.htaccess</code> in <code data-start="2917" data-end="2926">public/</code></td>
</tr>
<tr data-start="2943" data-end="3042">
<td data-start="2943" data-end="2961" data-col-size="sm">Default Example</td>
<td data-start="2961" data-end="3000" data-col-size="sm"><code data-start="2963" data-end="2985">http://localhost/ci/</code></td>
<td data-start="3000" data-end="3042" data-col-size="sm"><code data-start="3002" data-end="3026">http://localhost:8080/</code></td>
</tr>
</tbody>
</table>
</div>
</div>
<hr data-start="3044" data-end="3047" />
<h2 data-start="3049" data-end="3071">🎯 Best Practices</h2>
<ol data-start="3073" data-end="3459">
<li data-start="3073" data-end="3136">
<p data-start="3076" data-end="3136">Always set <strong data-start="3087" data-end="3099">Base URL</strong> correctly &rarr; Prevents broken links.</p>
</li>
<li data-start="3137" data-end="3190">
<p data-start="3140" data-end="3190">Remove <code data-start="3147" data-end="3158">index.php</code> &rarr; Cleaner, SEO-friendly URLs.</p>
</li>
<li data-start="3191" data-end="3314">
<p data-start="3194" data-end="3253">Use <strong data-start="3198" data-end="3218">.env file in CI4</strong> to manage <code data-start="3229" data-end="3238">baseURL</code> dynamically.</p>
<div class="contain-inline-size rounded-2xl relative bg-token-sidebar-surface-primary">
<div class="sticky top-9">
<div class="absolute end-0 bottom-0 flex h-9 items-center pe-2">
<div class="bg-token-bg-elevated-secondary text-token-text-secondary flex items-center gap-4 rounded-sm px-2 font-sans text-xs">
<pre class="language-php"><code>&lt;?php
$name = "John";
echo "Hello, " . $name; // Outputs: Hello, John
?&gt;</code></pre>
</div>
</div>
</div>
</div>
</li>
<li data-start="3315" data-end="3388">
<p data-start="3318" data-end="3388">For production &rarr; Set full domain (e.g., <code data-start="3358" data-end="3384">https://www.example.com/</code>).</p>
</li>
<li data-start="3389" data-end="3459">
<p data-start="3392" data-end="3459">Always enable <strong data-start="3406" data-end="3421">mod_rewrite</strong> in Apache (or equivalent in Nginx).</p>
</li>
</ol>
<hr data-start="3461" data-end="3464" />
<h2 data-start="3466" data-end="3483">✅ Conclusion</h2>
<ul data-start="3485" data-end="3776">
<li data-start="3485" data-end="3544">
<p data-start="3487" data-end="3544"><strong data-start="3487" data-end="3499">Base URL</strong> defines the root path of your application.</p>
</li>
<li data-start="3545" data-end="3595">
<p data-start="3547" data-end="3595"><strong data-start="3547" data-end="3561">Index Page</strong> can be hidden with <code data-start="3581" data-end="3592">.htaccess</code>.</p>
</li>
<li data-start="3596" data-end="3637">
<p data-start="3598" data-end="3637"><strong data-start="3598" data-end="3605">CI3</strong> &rarr; configured in <code data-start="3622" data-end="3634">config.php</code>.</p>
</li>
<li data-start="3638" data-end="3693">
<p data-start="3640" data-end="3693"><strong data-start="3640" data-end="3647">CI4</strong> &rarr; configured in <code data-start="3664" data-end="3673">App.php</code> (or <code data-start="3678" data-end="3684">.env</code> file).</p>
</li>
<li data-start="3694" data-end="3776">
<p data-start="3696" data-end="3776">Removing <code data-start="3705" data-end="3716">index.php</code> is essential for <strong data-start="3734" data-end="3748">clean URLs</strong> and <strong data-start="3753" data-end="3773">SEO optimization</strong>.</p>
</li>
</ul>

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