1280 × 720
YouTube thumbnail size, and a resizer to hit it
The specification is short: 1280 by 720 pixels, 16:9, under 2 MB. Drop an image below and get one that matches exactly.
Resized in your browser with Canvas · your image is never uploaded
What the numbers mean in practice
YouTube displays thumbnails at wildly different sizes — a few hundred pixels wide in a sidebar, nearly full width on a television. Uploading at 1280×720 gives the platform enough resolution to scale down cleanly everywhere without wasting file size.
The 2 MB ceiling is rarely a problem for a photo but easily broken by a PNG containing large flat areas of colour. If an upload is rejected for size, saving as JPG instead almost always solves it.
Anything not matching 16:9 gets bars added or edges trimmed by YouTube, and you do not get to choose which part survives. Matching the ratio before upload is the only way to control the framing.
Why text needs to be large
Most viewers meet your thumbnail at around 360 pixels wide on a phone. Text that reads comfortably at full size can become illegible at that scale. A practical test: shrink your thumbnail to a quarter of its size and see whether the words still work. If not, fewer and bigger is the fix.
Setting up a channel? The banner has its own specification and a safe area to respect — see YouTube banner size.
Common questions
What is the exact YouTube thumbnail size?
1280 by 720 pixels, a 16:9 ratio, under 2 MB.
Can I upload a larger image?
Yes. 1920×1080 works fine and keeps the same ratio. YouTube scales it down.
Why was my thumbnail rejected?
Almost always file size. Save as JPG rather than PNG to get under 2 MB.
Does this tool upload my image?
No. The resizing happens in your browser using Canvas. Nothing is sent anywhere.