How to preview a YouTube thumbnail
- Upload, drag in or paste your thumbnail image, or paste a YouTube link to load an existing video's thumbnail and title.
- Type your title and fill in the channel name, avatar, view count, upload age and duration.
- Switch between the Home, Search, Up next, Mobile and TV views, and toggle the light or dark YouTube theme.
- Turn on A/B compare to place two or three thumbnail and title variants in the same feed.
- Click Shuffle to move your video around the feed, then export the mockup as a PNG.
What you can do with Thumbnail & Title Previewer
- Five YouTube surfaces
- Realistic mockups of the desktop home grid, search results, the Up next sidebar, a phone feed and the TV interface, in light or dark theme.
- Compare up to 3 variants
- Show variants A, B and C in the same feed to see which thumbnail and title combination stands out from the crowd.
- Real competitor thumbnails
- Upload up to 12 thumbnails from your niche and edit their titles, so your video is judged against the competition you actually face.
- Size and format check
- Each upload shows its pixel size, whether it is 16:9, and whether the file is over YouTube's 2 MB thumbnail limit.
- Load from a YouTube link
- Paste any video link to pull its best available thumbnail plus the title and channel name for quick side-by-side comparisons.
- PNG export
- Save the current mockup as a PNG to share with an editor, a client or your team before you publish.
YouTube thumbnail size and best practices
A thumbnail is judged at very different sizes. On the desktop home feed it is around 300 pixels wide, in the Up next sidebar it can shrink to about 168 pixels, and on a TV it is viewed from across the room. Text that reads well in your editor can turn into a smudge in the sidebar. Previewing in context shows whether the main subject, faces and the two or three words on the image still work at small sizes, and whether your title gets cut off after two lines.
YouTube recommends custom thumbnails at 1280×720 pixels (16:9) with a minimum width of 640 pixels, saved as JPG, PNG or GIF and under 2 MB. Design at full resolution, keep important details away from the bottom-right corner where the duration badge sits, and check contrast in both light and dark themes. When you have several ideas, compare them in a crowded feed rather than on a blank canvas. Channels with access to Test & Compare in YouTube Studio can then test the strongest versions on real viewers.
Frequently asked questions
What size should a YouTube thumbnail be?
YouTube recommends 1280×720 pixels, a 16:9 aspect ratio and a minimum width of 640 pixels. The file should be JPG, PNG or GIF and no larger than 2 MB. This previewer flags images that are smaller than 1280×720, not 16:9, or over the 2 MB limit.
Are my thumbnails uploaded anywhere?
No. Images you upload or paste stay in your browser and are displayed from local memory. The only network requests happen when you load a thumbnail from a YouTube link, which fetches that image from YouTube, and when you export a PNG, which loads a small rendering library.
Can I A/B test YouTube thumbnails with this tool?
You can compare up to three thumbnail and title variants side by side in realistic feeds, which is a fast way to rule out weak ideas before publishing. It does not measure real click-through rate. For live testing on actual viewers, use Test & Compare in YouTube Studio if your channel has it.
How long can my title be before it gets cut off?
YouTube allows up to 100 characters, but most layouts show about two lines. The preview shows exactly where your title is truncated on each surface. As a rule of thumb, keep the key words within the first 60 to 70 characters, and use the title length checker for a detailed breakdown.
Does the thumbnail previewer work on mobile?
Yes. It runs in any modern browser on phones, tablets and computers. On a small screen the desktop mockups scale down, so a laptop or desktop gives the most accurate view of the home grid and search layouts, while the Mobile view shows the phone feed.