Image below minimum size

iMessage needs images at least 150 x 150 pixels. Apple recommends a minimum width of 900 pixels. Below these thresholds, the image is silently dropped and the preview falls back to text-only or shows the apple-touch-icon / favicon.

curl -sI https://example.com/your-image.jpg | grep -i content-length

Use 1200 x 1200 pixels for reliable display across iOS versions.

Image URL returns a 404

If og:image points to a missing file, iMessage generates a preview without an image. Open the image URL directly in a browser to check.

Common causes: - Relative paths instead of absolute URLs (/images/og.jpg vs https://example.com/images/og.jpg) - Typos in the filename - Image hosted on a domain that’s down or blocking requests - CDN misconfiguration after a deployment

GIF images don’t animate

iMessage shows only the first frame of GIFs. For animated content in previews, use og:video with MP4:

<meta property="og:video" content="https://example.com/preview.mp4">
<meta property="og:video:type" content="video/mp4">

HTTP instead of HTTPS

App Transport Security blocks HTTP resources. If your og:image uses http://, the image won’t load even if the page itself is HTTPS:

<!-- Image won't load -->
<meta property="og:image" content="http://example.com/image.jpg">

<!-- Image will load -->
<meta property="og:image" content="https://example.com/image.jpg">

File too large

Images over 1 MB may fail, especially on cellular connections. The sender’s device downloads the image directly with no proxy – large files are more likely to time out. JPEG at 80% quality is usually fine.

iOS version differences

Apple changes cropping behavior between iOS versions. An image that looked right on iOS 15 may crop differently on iOS 17.

• iOS 16+ introduced full-width previews requiring at least 2400 x 1256 pixels
• iOS 17 trends toward square cropping

A 1200 x 1200 square image survives all crop variations.

Diagnosis checklist

1. Open the og:image URL directly – does it load?
2. Check dimensions – at least 150 x 150, ideally 1200 x 1200.
3. Check URL scheme – HTTPS?
4. Check format – JPEG and PNG are reliable. GIF won’t animate. Avoid WebP and SVG.
5. Check file size – under 1 MB.
6. Test on the target iOS version – rendering varies.