How to Convert H.264 to H.265 or AV1: A Complete Beginner's Guide

Introduction

If your hard drive is filling up with movies, TV shows or home videos, converting H.264 videos to H.265 (HEVC) or AV1 can significantly reduce file sizes while maintaining excellent image quality. Modern video codecs are far more efficient than H.264, allowing you to store more content using less disk space and stream videos more efficiently.

I'm living in Australia and the so-called cost of living crisis has hiked the cost of hard disk drives. Ever since covid-19 and now the AI data center boom cost, the demand for disk space storage and it cost has ballooned so I am reluctant to buy more hard disk drives. Hence this article.

This guide explains the differences between H.264, H.265 and AV1, when you should convert your videos, which software to use, and the settings that deliver the best balance between quality, compression and encoding speed.

What is H.264?

H.264, also known as AVC (Advanced Video Coding), has been the world's most popular video codec for over a decade. It offers excellent compatibility with televisions, smartphones, tablets, web browsers and media players, making it the default format for Blu-ray discs, YouTube videos and countless streaming services.

Although H.264 still delivers excellent image quality, it is no longer the most storage-efficient codec available. Compared with newer codecs such as H.265 and AV1, H.264 files are generally much larger for the same visual quality.

What is H.265 (HEVC)?

H.265, also called High Efficiency Video Coding (HEVC), is the direct successor to H.264. It typically reduces video file sizes by 30–50% while maintaining similar visual quality.

H.265 has become popular for 4K Ultra HD video, HDR content and media libraries where storage efficiency is important. Many modern televisions, smartphones and media servers support H.265 hardware decoding, making playback smooth while saving valuable storage space.

For quite some time I was really opposed to converting my home videos to H.265 as I have some old PC's trucking along. However, I am finally biting the bullet as the disk spaced saved is just too good to pass up and I'll gradually move my super old computer equipment along. My old equipment has served me well but I can easily get them to do other things than view videos, eg, games emulation. Yeah, I love my old Commodore 64 games.

What is AV1?

AV1 is a modern, open-source video codec developed by the Alliance for Open Media. It delivers even better compression than H.265 in many situations while avoiding royalty licensing fees.

Streaming providers such as YouTube, Netflix and other online platforms increasingly use AV1 because it provides excellent image quality while significantly reducing bandwidth requirements. Although encoding AV1 takes longer than H.265, the smaller file sizes make it attractive for long-term archiving.

H.264 vs H.265 vs AV1

Choosing the best codec depends on your priorities.

H.264 offers the widest compatibility and fastest encoding but produces the largest files.

H.265 provides an excellent balance between compatibility, quality and storage savings, making it the preferred choice for most home media collections.

AV1 produces the smallest files and highest compression efficiency but requires considerably more processing power to encode.

For most users, H.265 is currently the best all-round solution, while AV1 is ideal for long-term storage if encoding time is less important.

Why Convert H.264 Videos?

Converting existing H.264 videos offers several benefits.

• Reduce video file sizes by up to 50%
• Store more movies on the same hard drive
• Lower NAS storage costs
• Improve streaming performance
• Reduce backup times
• Save bandwidth when sharing videos
• Future-proof your media library

For users with large movie collections, the storage savings alone can justify converting thousands of videos.