This ensures you don't just get the smallest file, but the best-optimized file from a reputable encoder. Summary Testing
But there is a catch: Sonarr (and its cousin Radarr) does not have a native "I only want x265" button. Without proper configuration, Sonarr will grab the first release that meets its quality profile—usually the more common, larger x264 file.
Many older or niche TV shows are only available in x264. New episodes often appear in x264 first (due to faster encoding speeds), with x265 releases following hours later. sonarr prefer x265
x265 files are often 30–50% smaller than x264 files of the same perceived quality. 4K Standard:
: Decoding x265 video requires modern hardware. Older streaming sticks, legacy smart TVs, and aging computers may struggle to play it. This ensures you don't just get the smallest
Purpose: Identify releases whose release title contains encoder/codec hints (x265, HEVC, 10bit, HDR terms). Sonarr can match custom formats to release titles for scoring.
Go to Settings > Custom Formats . Create a Format for x265: Add a new format and name it "x265/HEVC". Many older or niche TV shows are only available in x264
Set a if you want to strictly enforce x265 acquisitions (though leaving this at 0 is recommended so Sonarr can still grab x264 files as a fallback if no HEVC version exists). Click Save . Advanced Tweaks: Balancing Quality and Release Speed