What is VP9? Google's royalty-free video codec explained

The VP9 codec is an open-source, royalty-free video compression format developed by Google to stream high-resolution video over the internet without incurring patent licensing fees. Released on June 17, 2013, as the successor to VP8, VP9 served as the primary compression engine behind YouTube’s 4K and HDR streaming infrastructure for over a decade.

While commercial broadcast networks and mobile cameras embraced HEVC (H.265), Google deployed VP9 across web browsers and connected TVs. Understanding VP9 reveals why web video evolved into an open-source format race, why Safari users could not watch 4K YouTube for years, and how modern Macs handle standalone WebM files.

Why did Google develop the VP9 video codec?

In 2010, Google acquired On2 Technologies, the creator of the proprietary TrueMotion VP3, VP6, and VP8 video codecs. Google open-sourced VP8 and launched the WebM Project to provide a royalty-free media stack for HTML5 web video.

However, as displays shifted from 1080p to 4K resolution, VP8 lacked the mathematical efficiency required to compress Ultra HD video streams. The video industry’s formal standards body, the Joint Collaborative Team on Video Coding (JCT-VC), was finalizing High Efficiency Video Coding (HEVC / H.265), promising a 50% bandwidth reduction over H.264.

HEVC carried substantial licensing restrictions. As patent pools multiplied and royalty demands escalated, distributing video streams across third-party websites threatened web platforms with unpredictable licensing costs.

Google engineered VP9 to deliver compression efficiency directly comparable to HEVC while keeping the software implementation open-source under a BSD-style license. By standardizing the format under the WebM Project, Google guaranteed that developers, hardware vendors, and browser makers could encode and decode modern video without paying patent pools.

What is the difference between VP9 Profile 0 and Profile 2?

Like other modern compression standards, the VP9 specification organizes its capabilities into profiles. The two most important profiles for consumers and streaming engineers are Profile 0 and Profile 2.

VP9 Profile 0: The 8-bit SDR baseline

Profile 0 is the baseline implementation of VP9. It supports standard 8-bit color depth with 4:2:0 chroma subsampling. When YouTube began rolling out 1440p and 4K resolutions across web browsers in 2014, those streams were encoded in VP9 Profile 0. It provided a substantial bandwidth advantage over H.264, allowing desktop computers to stream 4K content at roughly 10 to 18 Mbps instead of 30 to 40 Mbps.

VP9 Profile 2: 10-bit color and HDR streaming

As High Dynamic Range (HDR) displays arrived, 8-bit color depth was no longer sufficient. Mapping HDR’s wide contrast ratios across only 256 color values causes color banding across gradients.

In 2015, Google introduced VP9 Profile 2, adding support for 10-bit and 12-bit color depth at 4:2:0 chroma subsampling. Profile 2 allowed YouTube to launch HDR streaming in late 2016, pairing 10-bit color quantization with the Hybrid Log-Gamma (HLG) and Perceptual Quantizer (SMPTE ST 2084 / PQ) transfer functions.

Profile 2 became the global foundation for free HDR video on the internet. However, because Profile 2 required decoders to handle 10-bit math across every pixel, early hardware that only supported Profile 0 could not decode YouTube HDR streams, causing displays to fall back to 8-bit SDR versions.

How did VP9 transform YouTube and web streaming?

To understand VP9’s real-world impact, consider the bandwidth demands of streaming video to millions of simultaneous viewers.

Independent evaluations, including a streaming study published by the Netflix TechBlog, confirmed that VP9 delivers roughly 35% to 45% bitrate savings compared to legacy H.264.

Animation

A keyframe, then only what changed

VP9 achieves these savings through flexible superblock partitioning. While H.264 is locked into rigid 16 × 16 pixel macroblocks, VP9 organizes frames into 64 × 64 superblocks that recursively split into 4-way quadtrees down to 4 × 4 pixel partitions. In flat regions of an image, such as a studio wall, a single 64 × 64 block replaces 16 individual H.264 macroblocks, eliminating repetitive header data and reserving bits for fine details.

Google used this efficiency to transform YouTube’s operations:

1. Resolution gating: YouTube began restricting resolutions above 1080p (such as 1440p, 4K, and 8K) almost exclusively to VP9 (and later AV1). If a browser requested a 4K stream using H.264, YouTube capped the playback resolution at 1080p to prevent content delivery networks from saturating.
2. Bandwidth tiering: Viewers on modest connections could watch 1080p 60 fps gaming streams and travel vlogs without buffering, because VP9 cut the required streaming bandwidth from 8 Mbps down to under 4.5 Mbps.
3. The WebM ecosystem: VP9 paired with the open-source WebM container and the Opus audio codec. This royalty-free combination enabled Wikipedia, Reddit, and independent video platforms to embed HTML5 video directly into web pages without paying licensing fees.

Why did Apple Safari resist VP9 for seven years?

Between 2013 and 2020, Mac owners faced an annoying limitation: visiting YouTube in Safari capped video resolution at 1080p, while opening the exact same YouTube link in Google Chrome or Mozilla Firefox unlocked 4K 60 fps playback.

This discrepancy was the result of a deliberate corporate standoff between Apple and Google:

• Apple’s Position: Apple was a founding member of MPEG LA and heavily invested in HEVC hardware development. Apple Silicon processors and Intel Macs featured dedicated hardware decoders for HEVC. Apple argued that VP9 lacked dedicated hardware acceleration on many chips, and decoding VP9 via software would burn excess CPU cycles and increase battery use.
• Google’s Position: Google owned the largest video platform on earth and refused to pay HEVC royalties. Google encoded all 4K YouTube uploads into VP9 and declined to generate duplicate 4K HEVC streams specifically for Safari.

For seven years, Apple avoided implementing VP9 decoding inside macOS’s AVFoundation framework or Safari. Mac users who wanted 4K YouTube had to run Chrome, which decoded VP9 through software.

The standoff ended in September 2020. With the release of Safari 14 alongside macOS 11 Big Sur, Apple introduced native VP9 decoding into WebKit and Safari, as documented in Apple’s Safari 14 Release Notes. This update enabled Mac users to watch 4K 60 fps and 4K HDR YouTube streams inside Safari.

How does Apple Silicon play VP9 video files?

Even though Safari can stream VP9 video from web pages, local file playback on macOS remains limited.

If you download a WebM file containing a VP9 video stream and attempt to double-click it in Finder, QuickTime Player displays an error stating the file is not compatible. As we explore in our guide on how to play WebM on a Mac, Apple never added a Matroska or WebM demuxer to its native AVFoundation desktop file player. QuickTime Player cannot open standalone WebM or VP9 files.

Furthermore, Apple Silicon Media Engines (M1 through M4) do not feature dedicated, fixed-function silicon blocks specifically for VP9 decoding. Apple Silicon media engines provide dedicated hardware decode and encode pipelines for:

• H.264
• HEVC (8-bit and 10-bit)
• Apple ProRes (on Pro, Max, and Ultra chips)
• AV1 (hardware decoding on M3 and M4 chips)

Because there is no fixed-function VP9 hardware block in the Media Engine, players opening a VP9 file on Apple Silicon decode the video using multithreaded CPU instructions (ARM NEON) or GPU compute shaders. Fortunately, Apple Silicon CPU cores are powerful enough that decoding 4K 60 fps VP9 in software requires only a modest fraction of CPU headroom, resulting in smooth playback without dropped frames.

How does VP9 compare to AV1 and HEVC?

Today, VP9 occupies the middle ground in video compression history. It helped bridge the transition from legacy 1080p H.264 video to modern 4K HDR streaming, but it is now being steadily superseded by newer technology.

The successor to VP9 is AV1 (AOMedia Video 1). When Google recognized that the industry needed a unified, royalty-free standard backed by major hardware manufacturers, it joined forces with Apple, Mozilla, Microsoft, Netflix, and Amazon to form the Alliance for Open Media. AV1 incorporates the core architectural concepts of VP9 while adding roughly 30% greater compression efficiency. To learn more, read our complete guide on AV1 on Mac.

If you encounter downloaded WebM clips, archived YouTube rips, or open-source tutorial files compressed in VP9, you do not need to convert them to MP4. To understand the relationship between file wrappers and compression standards, see our guide on what a codec is.

To play VP9 and WebM files on your Apple Silicon Mac, download MacLC from the download page. It is free and open-source, requires no terminal commands or plugins, and handles open-source video formats reliably.