Optimizing Your Media Library: How to Prefer x265 in Sonarr If you're running a home media server, storage space is always at a premium. Transitioning your library to x265 (HEVC)
By assigning a score, Sonarr will automatically "upgrade" an existing x264 file to an x265 version if it finds one later, helping you prune your library size over time. Important Compatibility Note
x265 files are often 30–50% smaller than x264 files of the same perceived quality. 4K Standard: sonarr prefer x265
The primary, and most compelling, reason to prefer x265 is storage efficiency. At identical visual quality, an x265 encoded file is typically 30-50% smaller than its x264 counterpart.
The primary argument for x265 is its superior compression. High Efficiency Video Coding (HEVC) can deliver the same visual quality as its predecessor, x264 (AVC), at roughly half the bitrate. For a Sonarr user, this means a 20GB season of a drama can be reduced to 10GB without a perceptible loss in clarity. Over a library of hundreds of series, this translates to terabytes of reclaimed storage, delaying the need for expensive new hard drives. Integration via Custom Formats Optimizing Your Media Library: How to Prefer x265
. If they don’t, your media server will have to "transcode" the video, which puts a massive heavy load on your CPU. Regex strings
This guide will walk you through setting up custom formats and quality profiles to ensure your library shifts toward the x265 standard. Why Prefer x265? 4K Standard: The Sales Pitch for x265: The
Sonarr combines these with release profile scores and intrinsic quality scores (e.g., resolution). Use total scores to ensure x265 > x264.