YouTube Thumbnail Size Guide (2025)

Thumbnail size directly affects click-through rate (CTR). This guide explains exact dimensions for YouTube videos and Shorts, plus design psychology used by top creators.

Why Thumbnail Size Matters More Than You Think

A thumbnail is not just an image — it is your video’s first impression. YouTube compresses and displays thumbnails differently across devices. Incorrect sizes lead to blur, cropping, and lower engagement.

Creators who follow proper thumbnail dimensions consistently see higher impressions and better CTR.

Recommended YouTube Thumbnail Size (Standard Videos)

  • 1280 × 720 pixels
  • Aspect ratio: 16:9
  • Minimum width: 640px
  • Maximum file size: 2 MB
  • Formats: JPG, PNG, WEBP

This resolution ensures your thumbnail looks sharp on TVs, desktops, tablets, and mobile devices.

YouTube Shorts Thumbnail Size Explained

Shorts thumbnails use a vertical format. Even though YouTube auto-selects frames, uploading a custom thumbnail improves branding.

  • 1080 × 1920 pixels
  • Aspect ratio: 9:16

Common Thumbnail Size Mistakes

  • Using low-resolution images
  • Wrong aspect ratio causing cropping
  • Too much text (unreadable on mobile)
  • Ignoring contrast and background

Thumbnail Size vs CTR (Click-Through Rate)

Correct size alone won’t guarantee clicks, but incorrect size almost guarantees fewer clicks. Sharp thumbnails build trust and professionalism.

Tools to Analyze & Improve Thumbnails

Final Thoughts

YouTube thumbnail size is a technical foundation. Combine correct dimensions with emotional design to maximize impressions and CTR in 2025.