Question 1

What size should a YouTube thumbnail be?

Accepted Answer

1280 by 720 pixels, 16:9, under 2MB. But YouTube displays it far smaller: around 360 pixels wide in the home feed and 168 pixels in the sidebar. Most thumbnails fail because they were designed at full size and never checked small.

Question 2

How many words should be on a YouTube thumbnail?

Accepted Answer

Four at most, and two or three is usually better. At 168 pixels wide there is not enough room for more to stay readable. Short words also let the letters run bigger, which is what keeps them legible.

Question 3

Is RateThumbnails free?

Accepted Answer

Every visitor gets 3 free ratings with no signup. After that, credits are $8 for 20. It is a one-time purchase, not a subscription, and credits do not expire.

Question 4

Can an AI predict my click-through rate?

Accepted Answer

No, and anything claiming otherwise is guessing. The score here is an opinion based on design criteria: whether the subject reads at small sizes, whether it stands out in a feed, whether the title and image say different things. It is guidance, not a prediction.

How good is your thumbnail?

Actual size

Your thumbnail on the YouTube homepage