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</div><hr /><div id="function.md5" class="refentry">
<div class="refnamediv">
<h1 class="refname">md5</h1>
<p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">md5</span> — <span class="dc-title">Calculate the md5 hash of a string</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.md5-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type">string</span> <span class="methodname"><strong>md5</strong></span>
( <span class="methodparam"><span class="type">string</span> <code class="parameter">$str</code></span>
[, <span class="methodparam"><span class="type">bool</span> <code class="parameter">$raw_output</code><span class="initializer"> = false</span></span>
] )</div>
<p class="para rdfs-comment">
Calculates the MD5 hash of <em><code class="parameter">str</code></em> using the
<a href="http://www.faqs.org/rfcs/rfc1321" class="link external">» RSA Data Security, Inc.
MD5 Message-Digest Algorithm</a>, and returns that hash.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-function.md5-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term"><em><code class="parameter">str</code></em></span>
<dd>
<p class="para">
The string.
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">raw_output</code></em></span>
<dd>
<p class="para">
If the optional <em><code class="parameter">raw_output</code></em> is set to <strong><code>TRUE</code></strong>,
then the md5 digest is instead returned in raw binary format with a
length of 16.
</p>
</dd>
</dt>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.md5-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
Returns the hash as a 32-character hexadecimal number.
</p>
</div>
<div class="refsect1 changelog" id="refsect1-function.md5-changelog">
<h3 class="title">Changelog</h3>
<p class="para">
<table class="doctable informaltable">
<thead>
<tr>
<th>Version</th>
<th>Description</th>
</tr>
</thead>
<tbody class="tbody">
<tr>
<td>5.0.0</td>
<td>
The <em><code class="parameter">raw_output</code></em> parameter was added.
</td>
</tr>
</tbody>
</table>
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.md5-examples">
<h3 class="title">Examples</h3>
<p class="para">
<div class="example" id="example-4846">
<p><strong>Example #1 A <span class="function"><strong>md5()</strong></span> example</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$str </span><span style="color: #007700">= </span><span style="color: #DD0000">'apple'</span><span style="color: #007700">;<br /><br />if (</span><span style="color: #0000BB">md5</span><span style="color: #007700">(</span><span style="color: #0000BB">$str</span><span style="color: #007700">) === </span><span style="color: #DD0000">'1f3870be274f6c49b3e31a0c6728957f'</span><span style="color: #007700">) {<br /> echo </span><span style="color: #DD0000">"Would you like a green or red apple?"</span><span style="color: #007700">;<br />}<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
</p>
</div>
<div class="refsect1 notes" id="refsect1-function.md5-notes">
<h3 class="title">Notes</h3>
<blockquote class="note"><p><strong class="note">Note</strong>:
<strong>Secure password hashing</strong><br />
<p class="para">
It is not recommended to use this function to secure passwords, due to the fast nature of this hashing algorithm. See
<a href="faq.passwords.html#faq.passwords.fasthash" class="link">here</a> for details.
</p>
</p></blockquote>
</div>
<div class="refsect1 seealso" id="refsect1-function.md5-seealso">
<h3 class="title">See Also</h3>
<p class="para">
<ul class="simplelist">
<li class="member"> <span class="function"><a href="function.md5-file.html" class="function" rel="rdfs-seeAlso">md5_file()</a> - Calculates the md5 hash of a given file</span></li>
<li class="member"> <span class="function"><a href="function.sha1-file.html" class="function" rel="rdfs-seeAlso">sha1_file()</a> - Calculate the sha1 hash of a file</span></li>
<li class="member"> <span class="function"><a href="function.crc32.html" class="function" rel="rdfs-seeAlso">crc32()</a> - Calculates the crc32 polynomial of a string</span></li>
<li class="member"> <span class="function"><a href="function.sha1.html" class="function" rel="rdfs-seeAlso">sha1()</a> - Calculate the sha1 hash of a string</span></li>
<li class="member"> <span class="function"><a href="function.hash.html" class="function" rel="rdfs-seeAlso">hash()</a> - Generate a hash value (message digest)</span></li>
</ul>
</p>
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