x265, also known as High Efficiency Video Coding (HEVC), is a video compression standard designed to succeed H.264/AVC (x264). It offers significantly better compression efficiency than its predecessor, meaning it can store or stream video at a much smaller file size without a noticeable decrease in video quality. This efficiency is crucial for media enthusiasts who want to save on storage costs and bandwidth without sacrificing video quality.

: High-definition x265 files are typically 40% to 60% smaller than their x264 counterparts.

Scroll down to the section at the bottom of the profile configuration window.

Now, because the qualities are viewed as equal, Sonarr will use your Custom Format scores (+100 for x265) as the primary deciding factor. Setting Size Limits to Filter Out Bloat

You will see your newly created x265 / HEVC format listed there.

Check the box for if you want Sonarr to replace your current library files when a matching x265 version appears on your indexers.

: If an x265 release has a higher score and fits within your quality profile constraints, Sonarr will automatically select it over an x264 alternative during its routine RSS feed scans.

In your Indexer settings, add resolve : True to prefer repacks and propers, but add x265 to your "Preferred" list only for groups like MeGusta.

Here, you will build a "Release Title" condition. This is a Regular Expression (Regex) that catches every variation of x265 naming conventions.

First things first, ensure you're running . V2 is ancient and unsupported. Older V3 versions can still use "Release Profiles," but upgrading to V4 is highly recommended for the full feature set and stability.

(?i)\b(x|h)\.?265\b|\bhevc\b

: 4K (UHD) and High Dynamic Range (HDR) content natively use the x265 codec.

If you want Sonarr to prioritize these space-saving releases automatically, you need to configure its custom formats or release profiles. This guide will walk you through exactly how to make Sonarr prefer x265, step-by-step. Why Prefer x265 in Sonarr?

For years, Elias had been a "Remux" purist—nothing but the highest bitrate, uncompressed 4K files. But then came the Great Storage Crunch of '26. His 100-terabyte NAS was gasping for air, the red warning lights blinking like distressed eyes. He had two choices: spend a fortune on new drives or embrace the efficiency of