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YouTube Thumbnail Preview

Add your thumbnail and title to see how they look on YouTube's home feed, search results, Up next sidebar and mobile screens at real size. Compare up to 3 options side by side. Your images are never sent to a server.

Last updated: 2026/10/18 Video Feedback & bug reports

Thumbnail images 0 / 3

Drag & drop your thumbnail

or

Ctrl+Vto paste (⌘+V on Mac)

JPG, PNG, WebP, GIF or HEIC (iPhone). Add up to 3 images and compare them as A, B and C

    Spec check

    Add an image to automatically check its aspect ratio, resolution, file size and format against YouTube's guidance.

    Video details

    0 / 100

    Long titles are cut off with "…" at the end of the second line. Put the most important words first so the title still makes sense when it's cut.

    Channel icon (optional)

    Without an icon, the first letter of your channel name is shown in a colored circle.

    Shown in the time badge at the bottom right. Leave it blank to hide the badge.

    Real-size preview

    Make sure the time badge at the bottom right and the red watched bar along the bottom edge (shown on videos people have partly watched) don't cover any text or faces in your thumbnail. Grayscale shows whether your text is readable without relying on color, and the blur test shows whether people can tell what the video is about at a glance.

    Each preview is shown at its actual size in CSS pixels (at 100% browser zoom). YouTube's layout changes with window width, device and app version, so treat the sizes as a guide.

    Desktop · Home feed

    Thumbnail ~360px wide

    Desktop · Up next (watch page sidebar)

    Thumbnail ~168×94px

    Mobile · Home feed

    Full screen width (390px-wide phone)

    Mobile · Compact list

    Thumbnail ~160×90px (history, playlists, etc.)

    Tiny

    ~120px wide (notifications, playlist panel, etc.)

    How to Use

    1

    Add your thumbnail images

    Drag and drop an image or click "Choose image". You can also paste a screenshot with Ctrl+V (⌘+V on Mac). Add up to 3 images to compare them side by side as A, B and C. No image at hand? Click "Sample image" to try the tool.

    2

    Enter the title and channel details

    Type your video title, channel name, views and upload date, and video length, and every preview updates instantly. Long titles are cut off with "…" at the end of the second line, just like on YouTube, and you can see roughly how many characters stay visible.

    3

    Check how it looks everywhere

    Review six real-size views: the desktop home feed, search results and Up next sidebar, the mobile home feed and compact list, and a tiny view. Switch the dark theme, time badge, watched bar, grayscale and blur test on and off to make sure nothing important is hidden or hard to read.

    About YouTube Thumbnail Preview

    The same YouTube thumbnail appears at very different sizes depending on where it shows up. On the desktop home feed it is around 360px wide, but in the Up next sidebar it shrinks to about 168px, and in compact lists on phones to about 160px (all approximate, depending on screen width). Text that looked crisp in your editor can easily become unreadable in a real feed. This tool places your unpublished thumbnail into YouTube-style layouts at close to real size so you can check it before going live. You don't need the URL of a published video, and your images are displayed only inside your browser, never sent to a server.

    For the full specs and design tips, see our guide to YouTube thumbnail size and design. To crop an image to 16:9, use the Image Cropper; to shrink the file size, the Image Compressor; and to turn WebP or other formats into JPG or PNG, the Image Converter. For tips on making images lighter without losing quality, read How to Shrink Images Cleanly. To loop part of a video while you study it, try the YouTube Repeat Player.

    Features

    • Six real-size viewsSee the desktop home feed, search results and Up next sidebar, the mobile home feed and compact list, and a tiny view, all at actual CSS-pixel size.
    • Compare up to 3 optionsLine up your options and compare them under the same conditions. Reorder or replace images with one click.
    • Title cut-off and spec checkSee roughly where your title gets cut off with "…", and automatically check aspect ratio, resolution, file size and format against YouTube's guidance.
    • No upload, fully privateImages are only displayed in your browser and never sent to a server, so unreleased thumbnails and projects stay private.

    Use Cases

    • Make 2–3 thumbnail drafts before publishing and see which one stands out most in a feed
    • Check that the text in your thumbnail is still readable at small mobile sizes
    • Make sure the time badge and watched bar don't cover faces or key text
    • Check that darker thumbnails don't blend into the background in dark mode
    • Rearrange the words in your title based on where it gets cut off

    FAQ

    Are my images uploaded anywhere?
    No. Images are loaded and displayed only inside your browser and are never sent to a server. They aren't sent to any external service either, so you can safely test unreleased thumbnails and projects. Your images are cleared when you close or reload the page.
    How accurate are the preview sizes?
    Each preview reproduces a common YouTube display size at actual CSS-pixel size: about 360px wide on the desktop home feed, about 360×202px in search results, about 168×94px in the Up next sidebar, and about 160×90px in compact mobile lists. YouTube's layout varies with window width, device, app version and design updates, so treat these as a guide. If your browser zoom isn't 100%, the previews will look larger or smaller too.
    What size and file size should a YouTube thumbnail be?
    According to YouTube's guidance (as of October 2026), thumbnails should be 3840×2160 pixels with a minimum width of 640 pixels, in a 16:9 aspect ratio, and in an image format such as JPG or PNG. Anything 16:9 at 1280×720 pixels or larger works well for most screens. The file size limit depends on the device you upload from: up to 50MB from a computer, and up to 2MB from the YouTube mobile app. YouTube used to state only a 2MB limit, so you will still see that number in many articles. All of these figures are a guide based on YouTube's guidance, and requirements can change, so check YouTube Help for the latest. This tool's spec check uses these figures as a guide.
    What happens if my image isn't 16:9?
    This tool shrinks the image to fit a 16:9 frame and fills the leftover space with black bars. On YouTube, too, a non-16:9 thumbnail may get black bars or have its edges cut off depending on where it appears. To avoid surprises, create your thumbnail at 16:9, such as 1280×720 or 1920×1080. You can crop an existing image to 16:9 with the Image Cropper.
    How do I make a thumbnail that is readable at small sizes?
    Keep the text short (about three or four words), and set it large in a bold typeface. Make the brightness difference between text and background clear, and add an outline or shadow so it stays readable when small. The time badge sits at the bottom right, so keep important text and faces away from that corner. Use the tiny view (about 120px wide) and the grayscale and blur tests in this tool to see whether your message still comes across at a glance.
    How is this different from "Test & compare" in YouTube Studio?
    YouTube Studio's "Test & compare" shows up to three thumbnails (and titles) to real viewers of a published video and picks the one with the most watch time. It is available only in YouTube Studio on a computer and requires advanced features, among other conditions. This tool is for checking how your thumbnails look before you publish, so it can't measure viewer response. A good workflow is to narrow your ideas down to three options here, then run "Test & compare" to see how real viewers respond.
    Can I use it on my phone?
    Yes. It works in mobile browsers, and you can pick images from your photo library. If a desktop preview or the mobile view (designed for a 390px-wide phone) doesn't fit on your screen, scroll sideways inside that preview's frame.

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    Related Guides

    YouTube Thumbnail Size and Design: Specs, File Limits, and Mobile Tips YouTube thumbnail specs after the 2025 update: 16:9, 3840×2160 recommended, up to 50MB from a computer or 2MB from the app, JPG/PNG/GIF. Plus how to set one and design tips for small screens.