How to change a YouTube thumbnail on mobile

Change a regular video thumbnail in the YouTube Studio app: Content, pencil, Edit thumbnail, Custom. Verify if Custom is missing. Stay under 2MB on mobile.

2026-08-22 2 min read ThumbnailsYouTubeGuides

You can swap a thumbnail from your phone. You do not need a laptop.

This is the YouTube Studio *app* path for a regular video. Not a Short. For Shorts, use [how to change a YouTube Shorts thumbnail](/blog/how-to-change-youtube-shorts-thumbnail). For pixels, use the [YouTube thumbnail size guide](/blog/youtube-thumbnail-size). For what YouTube paints over, use [YouTube thumbnail safe zones](/blog/youtube-thumbnail-safe-zones).

The taps

Open the **YouTube Studio** app and sign in.

Tap **Content**.

Find the video. Tap the pencil.

Tap **Edit thumbnail**.

Tap **Change**.

Pick an image from your camera roll. Save.

It can take a minute to show on the watch page. If it still looks old, pull to refresh.

![YouTube Studio video details with the pencil](https://cdn.swell.so/thumbly/blog/how-to-change-youtube-thumbnail-on-mobile/01-studio-content.png)

![Thumbnail menu. Change is the custom upload](https://cdn.swell.so/thumbly/blog/how-to-change-youtube-thumbnail-on-mobile/02-edit-thumbnail.png)

If Custom is missing

You are not verified yet. Custom thumbnails stay locked until YouTube has a phone number on the channel.

Open [youtube.com/verify](https://www.youtube.com/verify) on the same account. Finish the steps. Come back to the video and try Custom again.

Do not hunt for a hidden menu. If you only see auto frames, that is the verify wall.

If the upload fails

Mobile is picky about file size. The Studio app caps a thumbnail at **2MB**. Desktop allows **50MB**.

If the app rejects the image, it is usually the cap, not the pixels. Export a smaller JPG. Try again. Do not re-export at a new resolution just to dodge the error. Size is already covered in the [size guide](/blog/youtube-thumbnail-size).

While you are in there, keep faces and text out of the bottom-right. The duration badge still lands there. That is the [safe zones](/blog/youtube-thumbnail-safe-zones) post.

Need a file that already fits? [Thumbly's YouTube thumbnail generator](/youtube-thumbnail-generator) exports a 16:9 image you can save to the camera roll and upload from Custom.

FAQ

**How do I change it on my phone?** Studio app → Content → pencil → Edit thumbnail → Change.

**No Custom button?** Verify at youtube.com/verify.

**Upload fails?** You are over 2MB. Compress.

**Is this for Shorts?** No. Use the [Shorts-change guide](/blog/how-to-change-youtube-shorts-thumbnail).

**What size?** See the [size guide](/blog/youtube-thumbnail-size). This post is the taps.