YouTube Thumbnail Size: Pixels, Ratio and File Size Limit

The YouTube thumbnail size to use in 2026 is 3840 x 2160 pixels, a 16:9 image, and YouTube's minimum width is 640 pixels. Older size guides still quote 1280 x 720, which works but isn't the size YouTube's help page lists today. The file limit depends on where you upload from: 2 MB from a phone, 50 MB from a computer. Shorts, podcasts and A/B tests each add a rule of their own, covered below along with export steps and fixes for rejected uploads.

YouTube thumbnail size at a glance

As of September 2026, this is the YouTube thumbnail size and file limit for each type, from YouTube's own help pages:

YouTube gives JPG and PNG as examples of accepted formats. It also asks for a thumbnail "as large as possible", because the same image becomes the preview in the embedded player, and thumbnails show up at different sizes on different devices.

To get the height of any 16:9 image, divide the width by 16 and multiply by 9. For the recommended size, 3840 / 16 x 9 = 2160.

YouTube thumbnail size in pixels, from the minimum to 4K

Any 16:9 size from 640 pixels wide upward meets YouTube's minimum, so the choice comes down to how much detail you keep. These are the 16:9 sizes YouTube uses for video, and how each one works as a thumbnail:

YouTube thumbnail size 1920x1080

A 1920 x 1080 thumbnail is exactly 16:9, three times the minimum width, and larger than the 1280 x 720 floor for A/B tests. It's a good choice when your design app or template is set to 1080p, or when the file at 4K comes out too heavy to upload from your phone. It has half the width of the 3840 x 2160 size YouTube recommends, so export the larger version whenever the file allows it.

YouTube thumbnail size 4K

A 4K thumbnail is 3840 x 2160 pixels, the size YouTube's resolution chart labels 2160p (4K) and the size its thumbnail page now recommends. Design at 4K when you can, and save smaller copies from the same file for anywhere else you post. A 4K file is larger, so check it against the 2 MB limit before you upload it from the mobile app.

YouTube thumbnail size ratio: why 16:9

Video thumbnails should be 16:9, the same shape as the standard YouTube player on a computer. Export the image at exactly that ratio instead of uploading a 4:3 phone photo or a square graphic, so you decide what's in the frame.

• Long videos: 16:9, such as 3840 x 2160 or 1920 x 1080.
• Shorts: 9:16, such as 2160 x 3840. Give a vertical video a 16:9 custom image and YouTube swaps in its own 4:5 frame on Home, Explore and Subscriptions. Your image still shows in the watch feed, in watch history and off mobile.
• Podcast playlists: 1:1. The playlist that represents the show takes a square image, while each episode video keeps its own 16:9 thumbnail.

YouTube thumbnail size limit: 2 MB or 50 MB

The file size limit depends on the device you upload from. In the mobile app, a video thumbnail can be up to 2 MB and a podcast thumbnail up to 10 MB. Uploads from a computer can be up to 50 MB for all three types: videos, Shorts and podcasts.

A full 4K image saved as a PNG can be larger than 2 MB. If the app rejects it, you have three fixes:

1. Upload the same file from YouTube Studio on a computer, where the limit is 50 MB.
2. Save a JPG copy, which is often smaller than a PNG of a photo-heavy design.
3. Export at 1920 x 1080, which still clears every minimum YouTube lists.

Each channel also has a daily cap on custom thumbnail uploads. If you see "Daily custom thumbnail limit reached", try again after 24 hours. YouTube says the cap varies by country or region and channel history, and Community Guidelines strikes lower it.

Shorts and podcast thumbnail sizes

Shorts and podcasts each follow their own rules on top of the video specs.

Shorts: 2160 x 3840 at 9:16

You can add a custom Shorts thumbnail only from YouTube Studio in a computer browser, and only on a verified account.

1. Sign in to YouTube Studio and select Content in the left menu.
2. Click Shorts at the top, then open the Short you want to edit.
3. Under "Thumbnail", click Upload file and choose a 9:16 image.
4. Click SAVE. Changes can take a while to show up on YouTube.

Shorts can't be part of a thumbnail A/B test, so pick the frame you want before you publish.

Podcasts: a square show image plus 16:9 episodes

On YouTube, a podcast is a playlist, and every episode is a video in it. YouTube recommends 1280 x 1280 pixels for the square podcast thumbnail, which you add on the podcast's Details page in YouTube Studio. You need that square image before you can edit the podcast's details. Each episode still needs a normal 16:9 video thumbnail, so a podcast channel keeps two templates: one square cover for the show and one wide layout for episodes.

Before YouTube lets you upload a custom thumbnail

Custom thumbnails need phone number verification. YouTube lists them as an intermediate feature, which a channel gets after verifying a phone number, and daily limits are higher for channels with advanced features. To see what your channel has, open YouTube Studio on a computer, click Settings, then Channel, then Feature eligibility. A/B testing needs advanced features on top of that.

To add a thumbnail to a long video:

1. Sign in to YouTube Studio and select Content.
2. Click the video.
3. Under "Thumbnail", click Upload file, or Get suggestions to let YouTube make options for you.
4. Click SAVE.

Every custom thumbnail must follow YouTube's Community Guidelines. A thumbnail with sexual content, hate speech, violence or harmful content can be rejected and bring a strike, and repeat offenses can cost you custom thumbnails for 30 days. Thumbnails also fall under YouTube's spam policy, which bans maliciously misleading thumbnails that promise something the video doesn't deliver.

How to make a thumbnail at the right size

Start every design at 16:9 and at least 1920 x 1080, and keep the original file so you can export a 4K copy later. If you're starting from a description instead of a design file, here is the route in Toybox AI, which makes 16:9 video thumbnails only (no 9:16 Shorts covers):

1. Open YouTube Thumbnail Generator and sign in with a free account.
2. Fill in "Describe your thumbnail" (up to 1,500 characters), or only "Text on the thumbnail" if the words are all you have (80 characters at most). Add "Your photo" if your face should be in it.
3. Pick a Style, such as Educational ("Clean and trustworthy") or Gaming ("Neon energy and action"), and click "Create thumbnail". It makes one 16:9 image, usually in about 30 seconds.
4. Download the PNG and check its width and height. On a Mac, Preview shows both under Tools, then Adjust Size. Toybox doesn't set an exact pixel size for this tool, so confirm the file is at least 640 pixels wide, and 1280 x 720 or larger if you plan to A/B test it.
5. For an exact 4K file on a Pro plan, choose "Open in Smart Editor". Under "More options", set Shape to Wide 16:9 and Quality to 4K, type "Keep everything exactly the same." into "What should change?", and click "Apply edit". That returns 3840 x 2160 pixels. Smart Editor redraws the whole picture instead of enlarging its pixels, so read the text and check faces afterward.
6. If the file is over 2 MB and you upload from your phone, save a JPG copy or use YouTube Studio on a computer.

A thumbnail currently costs 80 credits in YouTube Thumbnail Generator, and the 4K pass in Smart Editor currently costs 110 more (see current prices). For what should go inside the 16:9 frame, read what makes a good thumbnail or browse podcast, vlog and gaming thumbnail ideas. Your channel's banner has different rules again: a 2560 x 1440 image with a small safe area, covered in the banner size and safe area guide.

Common thumbnail size mistakes