YouTube Format IDs

The gist compiles comprehensive YouTube itag/format codes, noting that HFR formats (up to 60 fps) lack non-HFR 1080p+ H.264/VP9 variants, while AV1 appears only on popular videos, always HDR, with high-bitrate HFR versions (~3-4× normal). Premium-only formats (e.g., 356) require a subscribed account, and YouTube now applies AI-driven super-resolution, adding “-sr” suffixes to upscaled resolutions.