Likely causes

Same root causes as Facebook’s wrong image issue, since Threads shares the crawler and cache:

1. Relative URL: og:image must be a full HTTPS URL. Relative paths like /images/og.jpg fail silently or produce unexpected results.
2. Image below 200 x 200px: ignored entirely. The crawler falls back to picking a random image from the page.
3. Multiple og:image tags: the crawler uses the first one. If a CMS plugin or theme injects its own og:image before yours, that one wins.
4. Cached old image: Threads shares Facebook’s cache (~7 days, sometimes longer).

Diagnosing

1. Sharing Debugger

Open the Facebook Sharing Debugger and check the “og:image” field. It shows exactly what Meta’s crawler is using for both Threads and Facebook.

2. Verify image URL is absolute and reachable

curl -A "facebookexternalhit/1.1" -I https://example.com/your-image.jpg

Need a 200 OK with a valid Content-Type. A 403, 404, or login redirect means the crawler can’t get to it.

3. Check for duplicate tags

curl -A "facebookexternalhit/1.1" https://example.com/page | grep -i "og:image"

Multiple tags? The crawler uses the first. Remove or reorder duplicates.

4. Check dimensions

• Minimum: 200 x 200px (ignored below this)
• Recommended: 1200 x 630px for best mobile display

The fix

1. Absolute HTTPS URL for og:image
2. Image at least 200 x 200px (ideally 1200 x 630)
3. Single og:image tag, or correct one first
4. Add og:image:width and og:image:height:

<meta property="og:image" content="https://example.com/correct-image.jpg">
<meta property="og:image:width" content="1200">
<meta property="og:image:height" content="630">

1. Sharing Debugger, “Scrape Again” two or three times
2. If image content changed but the URL stayed the same, use a new filename to force Meta’s CDN to fetch it fresh