# YouTube Thumbnail Size: 3840×2160 Is the Official Recommendation

- Canonical URL: https://oka-project.com/en/blog/youtube-thumbnail-size
- Published: 2026-10-09
- Author: oka (https://oka-project.com/en/about)
- Summary: YouTube's official thumbnail specs as checked in October 2026: 3840×2160 px for regular videos, 2160×3840 px for Shorts, the conditions for uploading a custom image, per-device file size limits, and where 1280×720 fits.
- Category: guide / Tags: YouTube, thumbnails, image size, image compression, Karuku

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When you make a YouTube thumbnail, it is easy to get stuck on whether 1280×720 px is fine or whether you need 3840×2160 px. **As of October 1, 2026, YouTube's official help recommends 3840×2160 px (16:9) for regular videos and 2160×3840 px (9:16) for Shorts.**

A recommended resolution is not a hard requirement, though. 1280×720 px still works as a 16:9 image. Keep your original, and choose based on the device you upload from, what you are doing, and the file size limit for the finished image.

> [!NOTE]
> **Decide first**: regular videos use landscape 16:9; Shorts use portrait 9:16. Treat the official recommended size and a practical lightweight preset as two different things.  
> **Checked on**: October 1, 2026, in YouTube's official "Add video thumbnails" help for computer and mobile. Where things appear in YouTube and how features work may change.

## YouTube's official specs at a glance (2026)

| Item | Regular videos | Shorts |
|---|---|---|
| Recommended resolution | **3840×2160 px** | **2160×3840 px** |
| Recommended aspect ratio | 16:9 (landscape) | 9:16 (portrait) |
| Minimum width | 640 px | 640 px |
| Main image formats | JPG, PNG, and others | JPG, PNG, and others |
| Upload limit from a computer | 50 MB | 50 MB |
| Upload limit from mobile | 2 MB for regular video thumbnails | Under current guidance, custom images can only be added in YouTube Studio on a computer |
| Uploading a custom image | When you meet the requirements, such as account verification | **Verified account + YouTube Studio on a computer** |

YouTube's help also gives 640 px as the minimum width for Shorts. And because the upload limit depends on the device, do not mix up the 2 MB limit for setting a regular video thumbnail from mobile with the 50 MB limit on desktop.

Source: [YouTube Help: Add video thumbnails (computer)](https://support.google.com/youtube/answer/72431?co=GENIE.Platform%3DDesktop&hl=en)

## 1280×720 vs. 3840×2160: what is the difference?

Both are 16:9. But **the number YouTube currently gives as its recommended resolution is 3840×2160 px.** 1280×720 px keeps the same landscape ratio at a lighter, practical size.

| Situation | What to do |
|---|---|
| You are making a new thumbnail for a regular video and your source image has enough resolution | Use the official 3840×2160 px recommendation as your baseline |
| You need to keep the file small, for example because of the mobile upload limit | Revisit the file format and compression quality first; if needed, consider scaling down to 1280×720 px or similar |
| Sharing a work-in-progress in chat or doing a test display | A lightweight 16:9 image such as 1280×720 px is easy to handle |
| Your source image is small | Enlarging it to 3840×2160 px does not bring back detail that was never there |

Saving a large image does not mean every viewer sees it at that resolution on every screen. Choose based on both the quality you need and the file size.

### When you are capped at 2 MB

When you upload a regular video thumbnail from mobile, YouTube gives a 2 MB limit. Do not assume that 2 MB means it has to be 1280×720 px. Try this first:

1. Make sure you have the aspect ratio you need, such as 16:9.
2. Export in a format that suits the image and the upload destination, such as JPEG for photo-heavy images.
3. If the saved file is over the limit, adjust the quality a little at a time.
4. If it is still over, reduce the dimensions only as far as your purpose allows.
5. Check the finished image at the size it will actually be shown, and look again at text, faces, and details.

File size varies with how detailed the image is and its format, even at the same dimensions. Do not apply a compression ratio from one source image to another.

For the general steps, see [How to Reduce Image File Size Without Ruining the Quality](https://oka-project.com/en/blog/reduce-image-file-size).

## Can you upload a custom thumbnail for Shorts?

**Yes, you can upload your own custom image for Shorts.** As of October 1, 2026, YouTube's help lists two conditions: your account must be verified, and **you must add it in YouTube Studio on a computer.**

The steps:

1. Sign in to YouTube Studio on a computer.
2. Open Content in the left menu and choose the Shorts tab at the top.
3. Select the Short and open its details.
4. Under Thumbnail, choose Upload file and select a 9:16 image.
5. Select Save. It can take a while for the change to show.

For Shorts, do not just stretch a landscape thumbnail vertically. You need to **re-lay out the important parts for a portrait composition.**

YouTube also notes that for vertical videos with a 16:9 custom thumbnail, some surfaces, such as Home, Explore, and Subscriptions, may replace it with an automatically generated 4:5 thumbnail. Treat "9:16 for Shorts," "16:9 for regular videos," and "how vertical regular videos are shown on some surfaces" as separate conditions.

Source: [YouTube Help: Add video thumbnails](https://support.google.com/youtube/answer/72431?co=GENIE.Platform%3DDesktop&hl=en)

## Where to put text, faces, and logos

Thumbnails are seen in many places, not just on the video page: in lists, in search results, and on different devices. Small text that is readable in your editor, where the image is large, may become unreadable once it is scaled down in a list.

- Keep the main subject, faces, or products where they are easy to spot.
- Do not pile on text, and check that it is readable when scaled down.
- Do not put important logos or text right at the edges, to allow for differences between surfaces.
- For a portrait Shorts image, do not reuse the landscape thumbnail's text layout; check it with the center of the 9:16 frame as your reference.

This does not mean YouTube guarantees a fixed "safe area" of so many pixels. It is an editing practice: check an actual preview to make sure nothing important gets cut off.

## What is Karuku's 1280×720 preset for?

[Karuku](https://oka-project.com/en/tools/image-resize), oka-project's image compression and resizing tool, has a lightweight, practical YouTube preset at 1280×720 px. **It is not a replacement for the official 3840×2160 px recommendation.**

If you already have a high-resolution finished image and it fits within the upload limit from your computer, there is no need to shrink it. Consider resizing when you want a copy for sending or working on, or when you need to keep the file size down.

## Three mistakes to check before remaking a thumbnail

| What happened | Likely cause to check first | What to do |
|---|---|---|
| Uploading works on a computer but the file is over the limit on a phone | The upload limit depends on the device | Prepare an export that meets the device's limit, and keep the original |
| The main subject of a landscape image gets cut off in Shorts | Simply reusing a 16:9 image for 9:16 | Crop a portrait version from the source and re-lay out the text and subject |
| Text is readable in the editor on a computer but not in lists | Small text, or placement right at the edges | Check again at a scaled-down size close to how it appears in a phone feed |

The basic rule: **do not reuse the same image for a regular video's lightweight preset and a dedicated Shorts image just by scaling it up or down.** What changes is not only the resolution but the composition.

## Pre-publish checklist

- Regular videos are composed at 16:9, Shorts at 9:16.
- You saved the finished image separately instead of overwriting the original.
- The file size fits the way you will actually upload it, from a computer or mobile.
- Text, faces, and the subject are still recognizable when scaled down.
- If you are setting a custom image for Shorts, you meet the conditions: a verified account and YouTube Studio on a computer.
- After saving in YouTube, the thumbnail actually shows up.

## FAQ

### Can I still use a thumbnail made at 1280×720 px?

Yes. It is a practical size that keeps the 16:9 ratio. But the official recommended resolution as of October 1, 2026, is 3840×2160 px.

### Does a thumbnail have to be under 2 MB?

Not across the board. The current help gives a 2 MB limit when uploading a regular video thumbnail from mobile, and a 50 MB limit for thumbnails for videos, Shorts, and so on uploaded from a computer.

### Can I use any image I want for Shorts?

Yes. With a verified account, you can upload an image from the Shorts edit screen in YouTube Studio on a computer.

### Will a 3840×2160 px image always look better?

Resolution alone does not decide that. Also check that text is readable when scaled down and that what you want to show is well placed.

## Official sources

- [YouTube Help: Add video thumbnails (computer)](https://support.google.com/youtube/answer/72431?co=GENIE.Platform%3DDesktop&hl=en)
- [YouTube Help: Add video thumbnails (Android)](https://support.google.com/youtube/answer/72431?co=GENIE.Platform%3DAndroid&hl=en)

For your finished YouTube thumbnail, **check the official recommended dimensions, then save it to suit the device you upload from, the file size limit, and how it actually looks.** Keep Karuku's practical lightweight preset and YouTube's official recommendation clearly separate.