This gist contains nearly all YouTube format ID information. The original owner is Agent Oak, with modifications by Martin Eesmaa. Agent Oak created the original gist on November 13, 2019, last updated May 5, 2021. Martin Eesmaa has maintained this fork since September 17, 2022. He joined the yt-dlp Discord server on April 3, 2026, with username martineesmaa. Last updated: August 20, 2026.

Format IDs, also known as itag or format codes, were historically specified with the fmt parameter (e.g., &fmt=22) in the URL after the video ID (deprecated?). Depending on video age or popularity, not all formats are available. The table lists resolutions from 4320p down to 144p, with codecs including AV1, VP9, H.264, and VP8, and container variants (MP4, WebM). HFR stands for "High Framerate" (up to 60 FPS), while non-HFR is limited to 30 FPS.

Notable points: Non-HFR 1080p+ H.264 and VP9 variants are not provided for HFR videos. Same IDs are reused for 360° videos. 1440p+ H.264 variants are only for 360° videos. AV1 variants are only for popular videos and can be HDR. AV1 HFR High variants have ~3-4 times the bitrate, rare even among AV1 videos. Format 571 has ~50% higher bitrate than 402. Format 356 requires YouTube Premium. Format 214 links to rare videos.

YouTube started using AI super resolution in late 2025 (Q4), adding -sr suffix for upscaled resolutions. Some videos have AV1 codecs for low views or recent uploads. Duplicate video IDs exist between m3u8 and https protocols, e.g., 270 (m3u8) equals 137 (https). Special thanks to dtlnor and gamer191 for reporting linked codes.