Preview your thumbnail across every YouTube feed and device — Home, Search, Suggested, Subscriptions, Channel and Watch — in light and dark themes before you publish.
Log in to preview thumbnails unlimited for free. It only takes a moment — no payment required.
Log In to ContinueFree account · No payment required
Join 6,200+ automation creators getting real strategies, niche breakdowns, CPM reports, and tool updates every week — for free.
No. Your thumbnail is loaded entirely in your browser as an in-memory object URL. It is never sent to the server, never written to disk, and is released automatically when you clear it or leave the page.
Home, Search, Suggested (up-next sidebar), Subscriptions, Channel page, and Watch page — across desktop, tablet, and mobile, in both YouTube light and dark themes.
Enable it under Display options. It draws the title-safe area (dashed border at 10% inset) and the bottom-right duration badge zone over your thumbnail, so you can confirm no important elements are covered.
Drop real JPG / PNG / WEBP images into public/yt-thumb-previewer/assets/stock/ for filler thumbnails and assets/avatars/ for channel avatars. The API scans those folders on each load automatically.