Free thumbnail tool · no sign-up

YouTube Thumbnail Checker

Check a thumbnail the way viewers see it: real sizes, a visual review of the image and title, and a free on-device 2× enhancement that keeps your design.

Have the original file? Upload instead

Drop your thumbnail here JPG, PNG or WebP · up to 12 MB

Privacy and image use

Importing connects to YouTube, which receives your IP address. Use an image you own or have permission to process. Technical checks and enhancement stay on this device.

Your thumbnail appears here.

Import a link, then enhance the image or review it with its title.

AI visual review

Your analysis will appear here.

Allow AI review, then select Get AI visual review to analyze your thumbnail and title.

Enhance image resolution

Run an AI upscaler on your device. It can refine edges and double the dimensions, but it cannot fix the idea, layout or title. Use Analyze for that feedback.

A small super-resolution model runs locally, using WebGL or WASM. First use downloads the model. It preserves the layout but can introduce artifacts: compare lettering and faces carefully. It cannot recover the original design file. Maximum input for enhancement: 1920px per side and 2.07 megapixels.

Higher resolution is useful when the source supports it.

YouTube recommends 3840 × 2160 for landscape video thumbnails and accepts up to 50 MB from desktop. That is an upload limit, not a target file size. If your thumbnail is already sharp, there may be nothing to enhance.

A 1280 × 720 upload becomes 2560 × 1440 with this 2× model. We do not stretch every image to 4K or claim to restore lost detail. Re-exporting a higher-quality original is preferable when you have it.

YouTube's current thumbnail guidance

Analyze + enhance

Improve the file without replacing your design

Paste a YouTube video link or upload your original image. Analyze reviews what the thumbnail communicates; Enhance doubles its dimensions locally. They solve different problems, and neither predicts how many people will click.

Analyze the thumbnail and title

Allow AI review to check the focal subject, small-screen readability, distracting details, and how the image supports your title. The response separates strengths, priority changes, upscaling advice, and a test you can run.

Compare before keeping an upscale

Enhance runs a 2× super-resolution model on your device. Inspect matching close-ups at the same scale, especially text and faces, then download the full PNG. Changes can be subtle on a clean image, and artifacts are possible.

Start with the best source available

A YouTube link imports a public thumbnail rendition, not your original design file. If you still have a larger original export, upload that instead. Upscaling cannot recover the original artwork or fix an unclear idea.

Before you replace a thumbnail

Compare the original and enhanced lettering at the same scale.
Check the thumbnail at a small size as well as on a larger display.
Keep a copy of the original. A larger file is not proof of better audience response.

You control what leaves your device

Enhancement and technical checks run locally. Importing a video link connects to YouTube. Only when you allow and request AI review are reduced image copies and the title sent to the AI service. Free reviews are rate-limited.

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4 ways to stream

From quick prep to full streaming workflows

These free utilities cover the small jobs around content creation. For continuous channels and team production, Upstream also supports 24/7 live streaming, pre-recorded live streams, multistreaming, and Live Studio broadcasts.

For this tool, the closest next step is 24/7 live streaming, so that workflow appears first below.

Start Streaming Free