What size is a YouTube thumbnail?

YouTube’s requirements, as its help states them

From YouTube Help, read on 1 October 2026:

• Verified accounts only. YouTube lets only verified accounts add custom thumbnails.
• Podcasts take a square, 1:1 thumbnail for the playlist.
• Through the API the same 50 MB limit applies, per the Data API reference.

Is 1280 × 720 still fine?

Yes. It is double YouTube’s 640-pixel minimum, it looks sharp on phones and computers, and it stays under the 2 MB limit for uploading from a phone. What the larger size adds is detail on big screens and TVs. If you make thumbnails at 1280 × 720 today, there is no reason to redo old ones; for new ones, export at 3840 × 2160 when you upload from a computer.

Checking a thumbnail before you upload

The same image appears large on the home feed and small beside a playing video, where the Up next list draws it about 168 pixels wide on a computer. What survives there is what gets noticed:

• One subject and three or four words at most. Fine print disappears first.
• Keep the bottom-right corner clear. The video’s length covers it.
• Check both themes. An edge that matches YouTube’s white or black background melts into it.
• Match the video. YouTube’s thumbnail and title tips ask for thumbnails that fit what viewers get, so they don’t leave early.

The free YouTube thumbnail tester shows a thumbnail on YouTube’s home feed, search and Up next at their real sizes, in light and dark, checks it against the rules above and exports a copy at 1280 × 720 under 2 MB or full size under 50 MB. Nothing is uploaded.

Then let YouTube pick between versions

YouTube Studio can A/B test up to three titles and thumbnails. It shows each to viewers, keeps the one with the highest share of watch time and usually finishes within two weeks. It runs on a computer and not for Shorts.

Making and uploading thumbnails with Mellow Hub

Mellow Hub’s Creative Studio makes a 16:9 cover at 1280 × 720 from a short brief, and Hub uploads the video to YouTube with it, alone or with Shorts, Reels and TikTok in the same post. Hub checks YouTube’s rules before anything is sent, such as the required title of up to 100 characters.

Hub is paid: plans start at $19 a month (Solo), after a 7-day trial with a card on file that costs nothing if you cancel before it ends, and a monthly plan's first month is 20% off. Publishing is unlimited on every plan, under a fair-use ceiling that stops automated floods (900 publications a month on Solo). One publication is one post on one account, so a post sent to five networks counts as five. There are no automatic overage charges.