YouTube Thumbnail Aspect Ratio Calculator
YouTube recommends 1280×720 thumbnails. 16:9 ratio, under 2MB, JPG/PNG/GIF/BMP.
Drop an image, get every social size at once
Centered smart crop, exported as PNG. No upload to a server.
YouTube thumbnail specs
YouTube thumbnails are 1280×720 (16:9), under 2MB, in JPG, PNG, GIF, or BMP format. Uploads larger than 2MB get rejected; smaller is fine but you lose detail at any size below 1280×720.
Thumbnails display at multiple sizes across YouTube. Full size on the watch page, smaller on the homepage and search results, even smaller as suggested videos in the sidebar. Design for the smallest size you expect to be seen at.
What makes a thumbnail click
The single biggest predictor of click-through-rate on YouTube is thumbnail clarity at the smallest display size. If a viewer can't tell what's happening in the thumbnail at 240×135 (the suggested-video size), the thumbnail isn't doing its job. Tight crops on faces, large readable text, and high contrast all win.
Do not center critical text
YouTube overlays a video duration timestamp in the bottom-right corner of every thumbnail. Avoid putting key text or faces there or they'll be partially covered.
How the calculator works
Math, resizing, and image cropping in one place. Free, no signup, no watermark.
Enter your dimensions
Type any width and height in pixels. We simplify the ratio with the greatest common divisor and tell you the closest standard match.
Resize without losing proportions
Switch to Resize. Keep the original ratio while scaling to a new width or height. Round to whole pixels with one click.
Or drop in an image
Image mode shows a smart-cropped preview for every social platform: Instagram, TikTok, YouTube, LinkedIn, Pinterest, and more.
Download the right size
Grab a single PNG at the exact dimensions you need, or download every social platform size at once as a ZIP.
Built for the work you actually do
Every social platform. Every common ratio. Image-aware so you see what gets cropped before you post.
Sizing for Instagram
Square, portrait, story, Reel. Instagram has four valid sizes and the wrong one gets your post cropped. Pick the platform, get the pixels.
YouTube videos and thumbnails
Videos at 1920×1080 or 3840×2160. Thumbnails at 1280×720. Shorts at 1080×1920. Get the right size without searching the YouTube docs.
TikTok and Reels covers
9:16 vertical at 1080×1920. Drop your cover art, download a perfectly cropped version that won't get squashed.
DSLR and stock photos
Original 3:2 photo, target 4:5 Instagram portrait? Resize without distortion. Center crop preview shows what gets cut.
Designing for screens
Build mockups that fit 16:9 monitors, 9:16 phones, or 21:9 ultrawides. Get pixel dimensions before you open Figma.
Bulk export for a campaign
One image, every social platform size. Drop it in image mode, hit download all. ZIP file with PNGs ready to post.
Social media aspect ratios in 2026
Every common social platform format with the recommended pixel size and ratio.
| Platform | Format | Pixels | Ratio |
|---|---|---|---|
| Square post | 1080 × 1080 | 1:1 | |
| Portrait post | 1080 × 1350 | 4:5 | |
| Landscape post | 1080 × 566 | 191:100 | |
| Story | 1080 × 1920 | 9:16 | |
| Reel | 1080 × 1920 | 9:16 | |
| TikTok | Video | 1080 × 1920 | 9:16 |
| YouTube | Video | 1920 × 1080 | 16:9 |
| YouTube | Shorts | 1080 × 1920 | 9:16 |
| YouTube | Thumbnail | 1280 × 720 | 16:9 |
| Feed post | 1200 × 630 | 191:100 | |
| Story | 1080 × 1920 | 9:16 | |
| Cover | 851 × 315 | 851:315 | |
| Square post | 1200 × 1200 | 1:1 | |
| Cover | 1584 × 396 | 4:1 | |
| X (Twitter) | Image post | 1600 × 900 | 16:9 |
| X (Twitter) | Header | 1500 × 500 | 3:1 |
| Standard pin | 1000 × 1500 | 2:3 | |
| Tall pin | 1000 × 2100 | 10:21 | |
| Snapchat | Snap / Story | 1080 × 1920 | 9:16 |
Last verified May 2026.
Other platforms
Pre-filled calculators for every social platform.
Frequently asked questions
What's the smallest size YouTube will accept for a thumbnail?
640×360 (16:9) is the technical minimum, but anything under 1280×720 looks soft. Always upload at 1280×720 or larger.
Why does my thumbnail look pixelated on YouTube?
Either you uploaded under 1280×720 or YouTube compressed it heavily during processing. Use 1280×720 PNG for sharpest results, JPG at 90+ quality if you need a smaller file.
Can I A/B test thumbnails?
Yes. YouTube Studio supports thumbnail A/B testing for channels with enough watch hours. Two or three thumbnail variants run simultaneously and the platform picks the winner based on click-through rate.
What is an aspect ratio?
Aspect ratio is the relationship between width and height, written as width:height. A 1920×1080 image has a 16:9 aspect ratio because 1920÷120 = 16 and 1080÷120 = 9. The ratio describes the shape of the rectangle, independent of size. A 1280×720 image is also 16:9.
How do I calculate the aspect ratio of an image?
Divide width by height to get the decimal ratio. To get the simplified form, find the greatest common divisor (GCD) of width and height and divide both by it. 1920÷1080 = 1.778, GCD(1920, 1080) = 120, so the ratio is 16:9. The calculator above does this instantly.
Is 1920×1080 a 16:9 aspect ratio?
Yes. 1920÷1080 = 1.778, which equals 16÷9. Full HD video, most monitors, and standard YouTube videos are all 16:9 at 1920×1080.
What aspect ratio is best for Instagram?
Instagram supports four ratios. Square 1:1 at 1080×1080 for feed posts. Portrait 4:5 at 1080×1350 for taller feed posts (recommended for organic reach). Landscape 1.91:1 at 1080×566 for wide posts. Vertical 9:16 at 1080×1920 for Stories and Reels.
What ratio should I use for TikTok?
TikTok uses 9:16 vertical at 1080×1920 pixels. The same applies to Instagram Reels and YouTube Shorts. One vertical export covers all three.
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