Is there really no subscription?

Right. No locked stickers, no watermark, no premium tier. Ads keep the app free, and they are never shown on the editing screen.

Does the cutout need internet?

No. It runs on your device and your photo is never uploaded. The processing model is downloaded once on first use.

What size does it save?

YouTube thumbnails are saved as 1280×720 JPG. You can also pick Shorts (9:16), channel banner (2560×1440) and square (1:1).

Do I edit a landscape thumbnail in portrait?

Yes. You never need to rotate your phone. The editor stays in portrait and shows the canvas at 16:9.

What happens to an unfinished thumbnail?

It is auto-saved as you go. On back, Thumbly asks whether to keep the draft, and you can continue from the home screen.

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YouTube thumbnail size guide: thumbnail, Shorts and channel banner dimensions

Blurry thumbnails and cropped banners are almost always a size problem. YouTube only asks for a handful of dimensions, but thumbnails, Shorts and banners each use a different ratio, which is where people get tripped up. This is the 2026 cheat sheet, plus the three things that actually go wrong when you make them on a phone.

YouTube thumbnail: 1280×720, 16:9

The recommended thumbnail is 1280 pixels wide by 720 tall, a 16:9 ratio. Minimum width is 640px and the file must be under 2MB in JPG, PNG, GIF or BMP. YouTube recompresses it into several sizes after upload, so what matters more than resolution is whether it still reads when it is tiny. In search results and the mobile feed, a thumbnail is about the size of your thumbnail.

Shorts cover: 9:16 vertical

Shorts are vertical, so the cover is too. In the Shorts feed viewers usually see the first frame of the video rather than the cover; the cover shows up on the Shorts tab of your channel page. 1080×1920 is plenty everywhere.

Channel banner: 2560×1440, safe area 1546×423

The banner is cropped differently on TV, desktop and mobile. Build it at 2560×1440, but the only region visible on every device is the central 1546×423. Anything that matters, like your channel name or upload schedule, has to sit inside that box. File size limit is 6MB.

Three things that go wrong on a phone

First, gallery photos are mostly 4:3, so cropping to 16:9 loses the top and bottom. Place the face in the middle. Second, editing a landscape canvas on a portrait screen makes it look small, and people set the text too small. Check it again in the home grid after saving. Third, apps save at different resolutions. Anything below 1280×720 will look soft.

On the Thumbly home screen tap 'YouTube 16:9' to open a 1280×720 canvas
Pick 'Shorts 9:16' for Shorts and 'Banner' for a 2560×1440 channel banner
Save writes a JPG at the exact size into Pictures/Thumbly in your gallery

Start with the right size

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