YouTube Thumbnail Size Checker
Use this free YouTube thumbnail size checker to test your image against YouTube's real upload rules (resolution, 16:9 ratio, 2 MB limit and format), then see it on a live YouTube home page, watch page, search page and phone before you publish.
Live YouTube preview
Your thumbnail sits in a realistic YouTube page next to other videos, so you can judge whether it stands out.
Fix it automatically
How to use the YouTube thumbnail size checker
Four quick steps take you from a draft image to an upload-ready file.
'/><rect x='120' y='56' width='400' height='248' rx='22' fill='rgb(30,30,34)' stroke='rgb(255,43,43)' stroke-width='4' stroke-dasharray='14 10'/><path d='M320 234V126M278 166l42-42 42 42' fill='none' stroke='white' stroke-width='12' stroke-linecap='round' stroke-linejoin='round'/><rect x='236' y='256' width='168' height='14' rx='7' fill='rgb(70,70,78)'/></svg>)
Add your thumbnail
Drag your image into the box, paste it with Ctrl+V, or enter a YouTube video link.
'/><circle cx='320' cy='164' r='92' fill='none' stroke='rgb(42,42,48)' stroke-width='22'/><circle cx='320' cy='164' r='92' fill='none' stroke='rgb(52,199,89)' stroke-width='22' stroke-linecap='round' stroke-dasharray='532 578' transform='rotate(-90 320 164)'/><text x='320' y='186' font-size='64' font-weight='700' fill='white' text-anchor='middle' font-family='Arial'>92</text><g fill='rgb(52,199,89)'><circle cx='214' cy='316' r='9'/><circle cx='292' cy='316' r='9'/><circle cx='370' cy='316' r='9'/></g><circle cx='448' cy='316' r='9' fill='rgb(255,176,32)'/></svg>)
Read the score
Green means ready, amber means risky and red means YouTube may crop or reject the file.
'/><rect x='60' y='40' width='520' height='280' rx='16' fill='rgb(15,15,15)' stroke='rgb(60,60,68)' stroke-width='3'/><rect x='60' y='40' width='520' height='34' rx='16' fill='rgb(40,40,46)'/><rect x='84' y='88' width='140' height='79' rx='8' fill='rgb(60,60,70)'/><rect x='250' y='88' width='140' height='79' rx='8' fill='rgb(255,43,43)' stroke='white' stroke-width='3'/><rect x='416' y='88' width='140' height='79' rx='8' fill='rgb(60,60,70)'/><rect x='84' y='186' width='140' height='79' rx='8' fill='rgb(60,60,70)'/><rect x='250' y='186' width='140' height='79' rx='8' fill='rgb(60,60,70)'/><rect x='416' y='186' width='140' height='79' rx='8' fill='rgb(60,60,70)'/></svg>)
Preview it live
Switch between Home, Watch page, Search and Mobile to see how your thumbnail looks beside other videos.
'/><rect x='190' y='36' width='260' height='146' rx='12' fill='rgb(60,60,70)'/><circle cx='360' cy='86' r='24' fill='rgb(255,255,255)' fill-opacity='.25'/><path d='M320 204v62M290 238l30 30 30-30' fill='none' stroke='rgb(255,43,43)' stroke-width='12' stroke-linecap='round' stroke-linejoin='round'/><rect x='200' y='290' width='240' height='44' rx='22' fill='rgb(255,43,43)'/><text x='320' y='320' font-size='22' font-weight='700' fill='white' text-anchor='middle' font-family='Arial'>1280 × 720 · JPG</text></svg>)
Fix and download
Press "Resize and compress" to get a 1280 × 720 JPG under 2 MB, ready for YouTube Studio.
YouTube thumbnail size and requirements
A reliable YouTube thumbnail size checker has to test the same rules YouTube applies at upload. These are the current requirements, which you can confirm in the YouTube Help Center.
'/><rect x='70' y='56' width='480' height='270' rx='10' fill='rgb(48,48,58)' stroke='white' stroke-width='3'/><rect x='456' y='288' width='88' height='32' rx='4' fill='rgb(255,43,43)' fill-opacity='.55' stroke='rgb(255,43,43)' stroke-width='2'/><text x='500' y='309' font-size='13' fill='white' text-anchor='middle' font-family='Arial'>Keep clear</text><path d='M70 36h480M70 28v16M550 28v16' stroke='rgb(154,154,165)' stroke-width='2'/><text x='310' y='26' font-size='18' fill='white' text-anchor='middle' font-family='Arial'>1280 px</text><path d='M40 56v270M32 56h16M32 326h16' stroke='rgb(154,154,165)' stroke-width='2'/><text x='20' y='196' font-size='18' fill='white' text-anchor='middle' font-family='Arial' transform='rotate(-90 20 196)'>720 px</text><text x='310' y='200' font-size='34' font-weight='700' fill='white' text-anchor='middle' font-family='Arial'>16:9</text><text x='310' y='352' font-size='14' fill='rgb(154,154,165)' text-anchor='middle' font-family='Arial'>Max 2 MB · JPG, PNG or GIF</text></svg>)
| Requirement | YouTube's rule |
|---|---|
| Resolution | 1280 × 720 pixels recommended, 640 pixels wide minimum |
| Aspect ratio | 16:9 |
| File size | 2 MB maximum |
| Formats | JPG, GIF or PNG |
Why a thumbnail size checker matters
Most viewers meet your video as a tiny picture in a crowded feed. A thumbnail with the wrong ratio gets cropped or letterboxed, and an image under 1280 pixels wide looks soft on a TV or large monitor. Running a YouTube thumbnail size checker before you publish takes ten seconds and removes both problems.
It also helps with the "file too large" error. YouTube rejects thumbnails over 2 MB, and a screenshot saved as PNG often passes that limit. The built-in compressor lowers JPG quality step by step until the file fits, so you keep as much detail as possible.
Design tips for readable thumbnails
- Keep important text and faces away from the bottom-right corner, where the video length badge sits.
- Use three or four words at most, in a heavy font with strong contrast against the background.
- Check the Watch page and Mobile previews. If you can still tell what the image shows at sidebar size, it will work on phones.
- Leave a small margin around the edges. YouTube layouts change by device, and edges are the first thing to be trimmed.
Frequently asked questions
What is the best YouTube thumbnail size?
The best size is 1280 × 720 pixels in a 16:9 ratio, saved as a JPG or PNG under 2 MB.
How does the YouTube thumbnail size checker work?
It reads the width, height, file size and format of your image in your browser and compares them with YouTube's upload rules. Your file is never sent to a server.
Can I check a thumbnail that is already live?
Yes. Paste the video link and the tool loads its public thumbnail and reports the resolution and ratio. File size can only be read from an uploaded file.
Why does YouTube say my thumbnail is too large?
YouTube accepts files up to 2 MB. Use the "Resize and compress" button to export a smaller JPG without changing the 16:9 shape.