How Are YouTube Thumbnails Made Today?

YouTube's help pages recommend custom video thumbnails at 3,840 by 2,160 pixels in a 16:9 shape, with a minimum width of 640 pixels, uploaded in a format such as JPG or PNG. You can choose from auto-generated suggestions, but uploading your own image requires a verified account.

Those specs are the easy part. In 2026, a thumbnail might be a frame picked from the video, an image designed in an editor, something generated by AI inside YouTube Studio, or a mix of all three, and then tested against alternatives. Here's how thumbnails are actually made today, step by step.

The rules and specs

According to YouTube Help, a custom thumbnail should:

• Be 3,840 by 2,160 pixels for videos (minimum width 640 pixels), or 2,160 by 3,840 for Shorts (minimum height 640 pixels).
• Use a 16:9 shape for videos, 9:16 for Shorts and 1:1 for podcast playlists.
• Use an image format such as JPG or PNG.
• Stay under the size limit for your device: 2 MB for video thumbnails on mobile, or 50 MB on desktop.
• Follow YouTube's Community Guidelines.

YouTube also says the image is used as the preview in the embedded player, so it recommends making it as large as possible.

Three ways thumbnails get made

1. Pick a frame. The simplest option is still a still from the video. On desktop, YouTube offers three suggested frames for long-form videos, and since July 2026 it does the same for Shorts. On mobile, you can pick any frame from a Short.
2. Design your own. Most bigger channels build thumbnails in an image editor. Chucky Appleby, who has made MrBeast's thumbnails since 2019, told The Ringer he started by reworking basic images with more colour and contrast and by making the face as large as possible. His test today is simple: "Could a grandma understand this? Could a kid understand this?"
3. Generate one with AI. In July 2026, YouTube added thumbnail generation to Ask Studio for long-form videos. You ask for a thumbnail for your latest video, then change colours and layouts by chatting, and YouTube says the results are tailored to the video's themes and your style. Its help pages add that Ask Studio analyses your video's transcript and themes to suggest thumbnails. Outside YouTube, a growing number of third-party tools also generate thumbnails from a prompt.

In practice, many creators combine these: they generate or sketch a few ideas, then finish the best one by hand.

Shorts finally get custom thumbnails

For years, Shorts creators could only choose a frame. On 24 July 2026, YouTube announced that YouTube Partner Program creators could start uploading custom thumbnails for Shorts, calling it a "top-requested feature", and said it would expand to more creators over time.

There are a couple of catches. DesignerOP, a design tools site, quotes YouTube Help as saying Shorts custom thumbnails can currently be added only in YouTube Studio on a computer and that the account must be verified. It also notes that if you put a 16:9 image on a vertical Short, YouTube can replace it with an auto-generated thumbnail in some places, so design Shorts covers in the 9:16 shape.

Testing: how the winner is picked

The biggest change in how thumbnails are made isn't a design tool. It's testing.

YouTube's Test & Compare feature, which began rolling out in June 2024 according to the YouTube Blog, lets creators test up to three thumbnails, three titles, or combinations of both. Here's how it works, based on YouTube Help and the YouTube Blog:

• Viewers are split into roughly equal groups, and each viewer keeps seeing the same version on the same account.
• The test runs until one version clearly earns a higher share of watch time, or for up to two weeks.
• Results come back as Winner, Performed Same or Inconclusive.
• If there's no clear winner, the first version you uploaded stays live, and you can change it manually at any time.

The key detail is the metric. YouTube says it optimises tests "for overall watch time over other metrics, like click-through-rate." It also notes that third-party tools often test versions one after another and optimise only for clicks, which can pick a different winner. Rene Ritchie, writing on the YouTube Blog, explained the thinking: watch time includes both the click and the viewing, so the tool rewards "thumbnails that make a promise and videos that deliver on it."

That's also why testing changed the look of thumbnails. As we cover in why so many YouTube thumbnails have shocked faces, MrBeast's own tests pushed him from open-mouthed expressions to closed-mouth smiles in 2023.

A practical workflow for 2026

Here's a sensible way for a small creator or seller to make a thumbnail today:

1. Decide the promise. Write one sentence on what the viewer will get, such as "see the jacket in the rain" or "fix the error in two minutes".
2. Capture a still while filming. A clean, well-lit frame of the product or result is often better than anything you'll make later.
3. Compose for a tiny screen. One clear subject, filling most of the frame, with strong contrast and only a few words, if any.
4. Check it small. Shrink the image to phone-thumbnail size. If you can't tell what it is in a second, simplify.
5. Export to spec. 16:9 for videos and 9:16 for Shorts, large enough and under the size limit.
6. Make two or three genuinely different versions. A different subject, crop or expression, not just a new colour.
7. Test where you can. If Test & Compare is available on your channel, let it run to a result rather than switching early.
8. Keep the honest one. If a version wins clicks but people leave quickly, it isn't really winning.

Common mistakes

• Misleading images. YouTube's 2012 guidance asked partners to upload images that represent the video, and its testing still rewards that.
• Too much text. Titles already sit next to the thumbnail, so repeating them wastes space.
• Wrong shape for Shorts. A wide image on a vertical video may not be shown where you expect.
• Forced expressions. Recent testing suggests natural faces often beat exaggerated ones.

The rest of this series

This is part two of our series on YouTube thumbnails. Part one asks why so many YouTube thumbnails have shocked faces. Part three looks at whether YouTube thumbnails still matter in 2026, and part four imagines what YouTube would look like with no thumbnails. If you're also making the video itself, see how whiteboard animation videos are made today.

How this was made: facts were gathered on 8 Oct 2026 (IST) from YouTube Help pages on thumbnails and A/B testing, the YouTube Blog (2012, June 2024 and July 2026), The Ringer (2026) and DesignerOP, then written up with AI help and checked line by line against those sources.

Sources

• 01support.google.com/youtube/answer/72431?hl=en
• 02support.google.com/youtube/answer/13861714?hl=en
• 03blog.youtube/news-and-events/youtube-studio-custom-thumbnail-updates/
• 04blog.youtube/creator-and-artist-stories/renes-top-five-june-14-2024/
• 05blog.youtube/news-and-events/expanding-custom-thumbnails-to-more/
• 06theringer.com/2026/03/09/pop-culture/youtube-face-thumbnails-history-explained
• 07designerop.com/blog/youtube-shorts-custom-thumbnail/

Related

• 01shoppercove.com/blog/vidrankr-product-clips-thumbnails-2026
• 02shoppercove.com/blog/shopify-product-page-video-checklist-october-2026
• 03shoppercove.com/blog/synthesia-syren-on-brand-ai-video-sellers-creators-october-2026