# Feature catalog — ytdl-org/youtube-dl

> Canonical page: https://codevetter.com/unpack/youtube-dl/feature-catalog

# Feature catalog — ytdl-org/youtube-dl

Scanned commit 956b8c585591b401a543e409accb163eeaaa1193 (2025-11-26). Generated by codevetter codevetter 1.12.0 on 2026-09-22.

User-facing surface = one CLI command `youtube-dl` with ~200 options defined in options.py plus the embeddable YoutubeDL API. Features cluster around: site extraction (~1200 supported sites), format/playlist/subtitle selection, sidecar file output (info JSON, description, annotations, thumbnails), ffmpeg-based postprocessing (audio extraction, recoding, embedding), authentication (username/password, netrc, video passwords, Adobe Pass TV providers), geo-restriction bypass, external downloaders, self-update, and simulation/printing modes for scripting.
- Site support: ~810 extractor modules under youtube_dl/extractor/ back roughly 1225 documented sites in docs/supportedsites.md; `--list-extractors` and `--extractor-descriptions` enumerate them at runtime via list_extractors(). — [youtube_dl/extractor/extractors.py](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/extractor/extractors.py) [docs/supportedsites.md](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/docs/supportedsites.md) [youtube_dl/__init__.py#L101-120](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/__init__.py#L101-L120)
- Format selection via `-f/--format` implements a mini-DSL (best/worst, format_id, filters like `[height<=?720]`, merge with `+`, fallback with `/`, groups) parsed by `YoutubeDL.build_format_selector` into selector functions. — [youtube_dl/YoutubeDL.py#L1312-1577](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/YoutubeDL.py#L1312-L1577) [youtube_dl/options.py](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/options.py)
- Playlist features include --playlist-start/--playlist-end, --playlist-items (comma list/ranges), --playlist-reverse, --playlist-random, --max-downloads, and --flat-playlist (extract_flat), implemented in __process_playlist. — [youtube_dl/YoutubeDL.py#L1108-1223](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/YoutubeDL.py#L1108-L1223) [youtube_dl/options.py](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/options.py)
- Subtitle support: --write-sub/--write-auto-subs/--all-subs/--list-subs download or enumerate subtitle tracks, with --sub-format and --sub-langs filtering in process_subtitles; --convert-subs converts to srt/ass/vtt/lrc via FFmpegSubtitlesConvertorPP. — [youtube_dl/YoutubeDL.py#L1872-1920](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/YoutubeDL.py#L1872-L1920) [youtube_dl/YoutubeDL.py#L2033-2066](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/YoutubeDL.py#L2033-L2066) [youtube_dl/options.py#L884-887](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/options.py#L884-L887)
- Audio extraction `-x/--extract-audio` appends an FFmpegExtractAudio postprocessor honoring --audio-format (best/aac/flac/mp3/m4a/opus/vorbis/wav) and --audio-quality; recoding via --recode-video maps to FFmpegVideoConvertorPP. — [youtube_dl/__init__.py#L259-270](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/__init__.py#L259-L270) [youtube_dl/postprocessor/ffmpeg.py#L40-48](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/postprocessor/ffmpeg.py#L40-L48) [youtube_dl/__init__.py#L207-216](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/__init__.py#L207-L216)
- Sidecar outputs: --write-info-json, --write-description, --write-annotations, --write-thumbnail/--write-all-thumbnails, and --xattrs (filesystem extended attributes) are all emitted from process_info/_write_info_json/_write_thumbnails. — [youtube_dl/YoutubeDL.py#L2001-2072](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/YoutubeDL.py#L2001-L2072) [youtube_dl/YoutubeDL.py#L2658-2713](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/YoutubeDL.py#L2658-L2713) [youtube_dl/postprocessor/xattrpp.py](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/postprocessor/xattrpp.py)
- --download-archive records `extractor_key + ' ' + video_id` lines (via _make_archive_id) into a text file; in_download_archive checks it inside _match_entry to skip already-downloaded videos; writes go through locked_file for interprocess safety. — [youtube_dl/YoutubeDL.py#L2341-2387](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/YoutubeDL.py#L2341-L2387) [youtube_dl/YoutubeDL.py#L823-824](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/YoutubeDL.py#L823-L824)
- Authentication options cover --username/--password (+ interactive getpass when password omitted), --twofactor, --netrc, --video-password, and Adobe Pass TV-provider login via --ap-mso/--ap-username/--ap-password with --ap-list-mso listing MSO_INFO providers. — [youtube_dl/__init__.py#L121-146](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/__init__.py#L121-L146) [youtube_dl/extractor/common.py#L1162-1222](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/extractor/common.py#L1162-L1222) [youtube_dl/extractor/adobepass.py](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/extractor/adobepass.py)
- Self-update: `-U/--update` invokes update_self(), which only applies to the zip/frozen builds, verifies a pinned RSA signature over versions.json, then sha256-checks and replaces the running binary (via a .bat swap on Windows). — [youtube_dl/update.py#L34-176](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/update.py#L34-L176) [youtube_dl/options.py#L139-141](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/options.py#L139-L141)
- Geo-bypass fakes an X-Forwarded-For header with a random IP drawn from per-extractor _GEO_COUNTRIES/_GEO_IP_BLOCKS or --geo-bypass-country/--geo-bypass-ip-block, with automatic retry on GeoRestrictedError inside InfoExtractor.extract. — [youtube_dl/extractor/common.py#L480-602](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/extractor/common.py#L480-L602) [youtube_dl/utils.py#L5629-5888](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/utils.py#L5629-L5888)
- External downloaders: --external-downloader selects among aria2c, aria2p (JSON-RPC library), axel, curl, ffmpeg/avconv, httpie and wget; each ExternalFD subclass builds a CLI via _make_cmd and runs it with subprocess.Popen; --external-downloader-args injects extra args. — [youtube_dl/downloader/external.py#L146-536](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/downloader/external.py#L146-L536) [youtube_dl/downloader/__init__.py#L48-55](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/downloader/__init__.py#L48-L55)
- Simulation/inspection modes: --simulate, --skip-download, --dump-json/--dump-single-json, --print-json, --get-url/--get-title/--get-id/--get-filename family, --list-formats and --list-thumbnails, plus --load-info-json to reprocess a saved info dict. — [youtube_dl/__init__.py#L248-249](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/__init__.py#L248-L249) [youtube_dl/YoutubeDL.py#L1921-1950](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/YoutubeDL.py#L1921-L1950) [youtube_dl/YoutubeDL.py#L2273-2285](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/YoutubeDL.py#L2273-L2285)
- Output templating `-o` supports %(field)s substitution over the info dict (plus `epoch`, `autonumber`), NA placeholders, numeric-field format patching, env-var/`~` expansion, and `outtmpl='-'` to stream media to stdout. — [youtube_dl/YoutubeDL.py#L704-791](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/YoutubeDL.py#L704-L791) [youtube_dl/utils.py#L4662](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/utils.py#L4662) [youtube_dl/utils.py#L2089-2094](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/utils.py#L2089-L2094)
- --exec CMD registers ExecAfterDownloadPP which substitutes `{}` with the shlex-quoted final filepath and runs the command through the system shell after all other postprocessing. — [youtube_dl/postprocessor/execafterdownload.py#L13-31](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/postprocessor/execafterdownload.py#L13-L31) [youtube_dl/__init__.py#L302-308](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/__init__.py#L302-L308)
- Rate/robustness controls: --limit-rate (throttling via FileDownloader.slow_down), --retries/--fragment-retries (incl. 'inf'), --sleep-interval/--max-sleep-interval randomized delays, --http-chunk-size segmented downloading, --buffer-size and --no-resize-buffer adaptive block sizing. — [youtube_dl/downloader/common.py#L178-192](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/downloader/common.py#L178-L192) [youtube_dl/downloader/common.py#L371-392](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/downloader/common.py#L371-L392) [youtube_dl/downloader/http.py#L282-316](https://github.com/ytdl-org/youtube-dl/blob/956b8c585591b401a543e409accb163eeaaa1193/youtube_dl/downloader/http.py#L282-L316)

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