- Free, no sign-up
- Nothing leaves your browser
- Sizes checked Sep 2026
Check your social images before they go out.
See how one image crops on LinkedIn, Instagram, Google and in email, check that any text on it can be read, then download every size.
Drop an image, or paste one
JPG, PNG, WebP or GIF. It never leaves your device.
- Add an image
- Drag over what matters
- Download each size
Quick reference
Social image sizes, September 2026.
The sizes the tool checks against. We review them every quarter, when we update our own templates.
| Format | Size (px) | Ratio |
|---|---|---|
| LinkedIn feed post | 1080 × 1350 | 4:5 |
| LinkedIn link card | 1200 × 627 | 1.91:1 |
| LinkedIn page coverKeep the left 340px clear. The logo covers it on mobile. | 1128 × 191 | 5.91:1 |
| Instagram feed post | 1080 × 1350 | 4:5 |
| Instagram profile gridThe grid shows a 3:4 crop of every post. | 1080 × 1440 | 3:4 |
| Instagram story or reelKeep text between the dashed lines, away from the app’s buttons. | 1080 × 1920 | 9:16 |
| Google Business update post | 1200 × 900 | 4:3 |
| Google Business cover photoSearch results may crop it to a square, so keep the subject centred. | 1080 × 608 | 16:9 |
| Email newsletter imageAny ratio. It displays at 600px wide, so 1200px keeps it sharp. | 1200 wide | Any |
Questions
Good to know.
What size should a LinkedIn post image be?
1080 × 1350 px (4:5) takes up the most space in the feed. Link previews use 1200 × 627 px (1.91:1), and the company page cover is 1128 × 191 px.
What size is an Instagram post in 2026?
1080 × 1350 px (4:5) for feed posts and 1080 × 1920 px (9:16) for Stories and Reels. The profile grid shows a 3:4 crop of each post, so keep the subject away from the top and bottom edges.
Is my image uploaded anywhere?
No. Your browser reads the image on your device and it never leaves it. The downloads are made on your device too. Close the tab and it’s gone.
How does the text contrast check work?
Drag over text in your image. The tool finds the two main colours in that area and scores them against WCAG 2.2, which needs 4.5:1 for body text, and APCA, the draft method for WCAG 3.
Why does my image look blurry after posting?
Usually it was smaller than the recommended size, or over 5 MB, so the platform enlarged or recompressed it. The tool flags both before you post.
How we keep these current
We review every platform size every quarter, when we update our own templates. If you spot something out of date, email info@onmark.com.au and we’ll fix it that week.
Rather have it done properly?
We build brand systems and social templates that pass these checks from the start.