Available Thumbnail Resolutions
Our downloader fetches all available quality levels directly from YouTube's servers: • Default (120×90 px) — small, low quality, always available • Medium Quality (320×180 px) — mqdefault • High Quality (480×360 px) — hqdefault • Standard Definition (640×480 px) — sddefault • HD Thumbnail (1280×720 px) — maxresdefault (most common max) • Full HD / Max Resolution (up to 1920×1080) — when available Note: 4K thumbnails are only available for videos where the creator uploaded a custom high-res thumbnail.