Free image resizer
YouTube thumbnail resizer
Crop an image for a video thumbnail (16:9), a Shorts thumbnail (9:16), your channel banner (2560 × 1440) or profile picture. In your browser.
- Free
- No sign-up
- Runs in your browser
Small enough for YouTube's 2 MB limit when uploading from a phone; from a computer it takes up to 50 MB.
Source: the platform's help page
Drop an image here
Resized in your browser and never uploaded.
How it works
- 1
Pick the platform and what the image is for: a post, a Story, a banner or a thumbnail.
- 2
Drop your image and drag it to choose what stays in the frame, or fit it whole on a background.
- 3
Download it at the exact size, as JPG or PNG.
Image sizes per platform
The sizes the resizer makes, each with where it comes from: the platform's own page wherever it publishes one.
| Platform | For | Size | Shape | Source |
|---|---|---|---|---|
| YouTube | Thumbnail (HD) | 1280 × 720 | 16:9 | the platform's help page |
| YouTube | Thumbnail (4K) | 3840 × 2160 | 16:9 | the platform's help page |
| YouTube | Shorts thumbnail | 1080 × 1920 | 9:16 | the platform's help page |
| YouTube | Profile banner | 2560 × 1440 | 16:9 | the platform's help page |
| YouTube | Profile picture | 800 × 800 | 1:1 | an industry guide |
Checked 6 November 2026.
Tips
- Tip 1For Instagram's feed, 4:5 portrait (1080 × 1350) takes the most room on a phone.
- Tip 2Keep text and faces away from the edges of covers and banners: phones and computers crop them differently.
- Tip 3Use PNG for text and logos, JPG for photos.
Use it from an AI app
ChatGPT, Claude and other AI apps can run this too, through the free API or the free MCP server. No account or key needed.
API
curl "https://superbridger.com/api/tools/image-sizes?platform=instagram"
JSON in, JSON out, open to any site (CORS). The OpenAPI description lists every endpoint. OpenAPI
MCP server
https://superbridger.com/api/tools/mcp → get_image_sizes
Add https://superbridger.com/api/tools/mcp as a custom connector in Claude, or as an app in ChatGPT. No sign-in.
FAQ
Questions
What size is a YouTube thumbnail?
16:9, at least 640 pixels wide, as large as 3840 × 2160. Small enough for YouTube's 2 MB limit when uploading from a phone; from a computer it takes up to 50 MB.
Can a Short have its own thumbnail?
Yes: 9:16, such as 1080 × 1920. YouTube takes Shorts thumbnails in YouTube Studio on a computer, from a verified account.
What size is a YouTube banner?
2560 × 1440 (at least 2048 × 1152, up to 6 MB). Only the middle 1235 × 338 shows on every device.
Is my image uploaded?
No. It's resized in your browser and saved straight to your device.
What happens to the parts that don't fit?
They're cropped. Drag the image to choose which part stays, and zoom in if you like. Or choose Fit to keep the whole image on a background colour.
More free tools
- Video checkerWill your video post on Reels, TikTok, Shorts, LinkedIn and X? Length, size, shape, codec and sound, per platform.
- Caption checkerOne caption against every platform's limit, counted the way each one counts: X's 280, Instagram's 5 hashtags, YouTube's title.
- Social media specsEvery limit in one dated table: video length and size, caption length, hashtags, photos and Stories. Also as JSON.
- Image resizerCrop an image to the right size for each platform: posts, Stories, banners and thumbnails. In your browser.
- Safe zone checkerSee where the buttons and captions of Reels, TikTok and Shorts cover your video, before you post.
- UTM builderTag a link for every platform at once, so your analytics show which post brought the visitors.
Post everywhere, starting today.
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Superbridger runs these checks before every post, then publishes to every platform at once.