> For the complete documentation index, see [llms.txt](https://docs.toomuchmedia.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.toomuchmedia.com/setup/nats-version-history-and-compatibility.md).

# NATS Version History & Compatibility

Welcome to the NATS version history guide. This reference matrix outlines the evolution of NATS releases, tracking PHP compatibility, database support milestones, distribution methods, and the specific Git/CVS targets associated with each release.

**If you have any questions about your current NATS version or its compatibility, please submit a support ticket before making any changes.**

<table><thead><tr><th width="134">NATS Version</th><th width="159">PHP Compatibility</th><th width="319">PHP-Specific Release Tags (if applicable)</th><th width="124">Distribution</th><th width="233">MySQL Compatibility</th></tr></thead><tbody><tr><td><a href="/pages/xZCD4NvTjclSVFLJ8Fs4#id-5.1.2.7"><strong>5.1.2.7</strong></a></td><td>PHP 7.1.x – 8.2.x</td><td></td><td>Git</td><td>MySQL 5.7.8 – 8.3</td></tr><tr><td><a href="/pages/xZCD4NvTjclSVFLJ8Fs4#id-5.1.1.4"><strong>5.1.1.4</strong></a></td><td>PHP 7.1.x – 8.2.x</td><td></td><td>Git</td><td>MySQL 5.7.8 – 8.0.32</td></tr><tr><td><a href="/pages/xZCD4NvTjclSVFLJ8Fs4#id-5.1.1.1"><strong>5.1.1.1</strong></a></td><td>PHP 7.1.x – 8.1.x</td><td></td><td>Git</td><td>MySQL 5.7.8 – 8.0.32</td></tr><tr><td><a href="/pages/xZCD4NvTjclSVFLJ8Fs4#id-5.0.4.4"><strong>5.0.4.4</strong></a></td><td>PHP 7.1.x – 8.1.x</td><td></td><td>Git</td><td>MySQL 5.1 – 8.0.32</td></tr><tr><td><a href="/pages/xZCD4NvTjclSVFLJ8Fs4#id-5.0.4.1"><strong>5.0.4.1</strong></a></td><td>PHP 7.4.x – 8.1.x<br><br>PHP 7.1.x – 7.4.x</td><td><code>REL_NATS_5_0_4_1_PHP8</code><br><br><code>REL_NATS_5_0_4_1_PHP7</code></td><td>Git</td><td>MySQL 5.1 – 8.0.32</td></tr><tr><td><a href="/pages/xZCD4NvTjclSVFLJ8Fs4#id-5.0.3.1"><strong>5.0.3.1</strong></a></td><td>PHP 5.6.x – 7.4.x</td><td><code>REL_NATS_5_0_3_1</code></td><td>Git</td><td>MySQL 5.1 – 5.7</td></tr><tr><td><a href="/pages/xZCD4NvTjclSVFLJ8Fs4#id-5.0.2.7"><strong>5.0.2.7</strong></a></td><td>PHP 5.6.x – 7.3.x<br><br>PHP 5.5.x – 5.6.x</td><td><code>REL_NATS_5_0_2_7</code><br><br><code>REL_NATS_5_0_2_7_PHP55</code></td><td>Git</td><td>MySQL 5.1 – 5.7</td></tr><tr><td><strong>5.0.0.1</strong></td><td>PHP 5.6.x – 7.3.x<br><br>PHP 5.5.x – 5.6.x</td><td><code>REL_NATS_5_0_0_1</code><br><br><code>REL_NATS_5_0_0_1_PHP55</code></td><td>Git</td><td>MySQL 5.1 – 5.7</td></tr><tr><td><strong>4.1.22.2</strong></td><td>PHP 5.6.x – 7.3.x<br><br>PHP 5.3.x – 5.6.x</td><td><code>REL_NATS_4_1_22_2</code><br><br><code>REL_NATS_4_1_22_2_PHP53</code></td><td>Git</td><td>MySQL 5.1 – 5.7</td></tr><tr><td><strong>4.1.22.1</strong></td><td>PHP 5.6.x – 7.3.x<br><br>PHP 5.3.x – 5.6.x</td><td><code>REL_NATS_4_1_22_1</code><br><br><code>REL_NATS_4_1_22_1_PHP53</code></td><td>CVS</td><td>MySQL 5.1 – 5.7</td></tr><tr><td><strong>4.1.21.1</strong></td><td>PHP 5.3.x – 5.6.x</td><td><code>REL_NATS_4_1_21_1</code></td><td>CVS</td><td>MySQL 5.1 – 5.6</td></tr><tr><td><strong>4.1.8.1</strong></td><td>PHP 5.2.x</td><td><code>REL_NATS_4_1_8_1_OLD_ENCODING</code></td><td>CVS</td><td>MySQL 5.1 – 5.6</td></tr></tbody></table>


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