YouTube Thumbnail Checker

A YouTube thumbnail checker tests an image against YouTube's requirements: 1280 by 720 minimum, 16:9 ratio and a 2 MB limit. It also previews the image, so you can judge it at small size.

It runs entirely in your browser. Nothing you paste or upload is sent to a server or stored.

How to read the result and act on it

Start with the pass or fail lines for size, ratio and file weight. A thumbnail that is at least 1280 by 720, in 16:9 and under 2 MB meets YouTube's requirements. If it fails, resize or export again at a higher quality setting, then re-check. After that, use the preview to judge the design at small size, because most viewers will see it as a tiny image in a feed. Ask whether the focal point is clear, whether any text is readable, and whether a bright or busy corner hides the video length label that sits in the lower right. If the image fails these tests, simplify: fewer words, one clear subject and strong contrast.

Common mistakes to avoid

The most common error is designing at a small size and then enlarging, which produces a blurry image even when the pixel count passes. Another is putting text near the bottom right where the timestamp overlay sits. Crowded thumbnails with several faces, arrows and lines of text look fine on a monitor and unreadable on a phone. Do not repeat the exact words of the title in the thumbnail, since both appear together and the repeat wastes space. Avoid images that promise something the video does not show. Finally, check that the file format is one YouTube accepts, such as JPG or PNG, and save a copy of the original in case you need to edit it.

What size should a YouTube thumbnail be?

1280 by 720 pixels, 16:9, under 2 MB, in JPG, PNG or GIF.

What makes a thumbnail work?

One clear subject, readable text at small size and a promise that matches the title.

What is the best thumbnail size for YouTube?

YouTube's guidance is 1280 by 720 pixels with a 16:9 ratio, under 2 MB. Larger images in the same ratio also work as long as they stay under the file limit. Format options include JPG, GIF and PNG.

Why does my YouTube thumbnail look blurry?

Blur usually comes from a low-resolution source that was enlarged, heavy compression to meet the file limit, or text that is too small. Design at 1280 by 720 or larger, export at a good quality setting and check the result at small size.

• YouTube Title Checker: Check a title's length, keyword position, caps and punctuation before you upload.
• YouTube Banner Checker: Check a channel banner's size and see the safe area for all devices.
• YouTube Thumbnail Links: Get the standard thumbnail image URLs for any YouTube video, from small to max resolution.

Browse all 20 free youtube tools, or see the full free SEO toolbox. If you would rather have this handled for you, take a look at our YouTube SEO services and the results from real projects.