Comparisons
Best Format for Google Discover and Social Previews
Images used in Discover and social previews need to look strong in a small card while staying efficient enough for mobile-heavy distribution.
Prepare the representative image before the metadata
For site-controlled delivery, compare WebP with JPG or PNG and inspect the result. Social crawlers and downstream platforms can have different format support, so verify their current preview behavior before standardizing the share copy.
Build for eligibility, then judge the preview
Separate two questions for a distribution image: can the platform fetch and use it, and does it look good after cropping? Correct metadata and crawl access answer the first. A clear subject, safe margins, and an appropriate source size answer the second. A beautiful file hidden behind the wrong URL is still no preview at all.
Platform behavior and crawler support can change, so use the figures here as workflow starting points and verify against current first-party guidance. For Google Discover, image eligibility does not guarantee appearance or traffic. For social cards, use each platform's preview or debug tool because the fetched result matters more than the design canvas.
Separate Discover eligibility from social-card crops
Google and social platforms publish different image guidance and can change card behavior. Use current first-party documentation for eligibility, then create the crop that preserves the subject in each important surface. A common wide share image can be a useful master, but it does not guarantee every card or Discover appearance.
For Discover, a large high-quality in-article image and permission for a large preview are relevant technical checks, not a promise of traffic. For social sharing, validate the fetched Open Graph or platform-specific image after the page is public.
- Check current Google image eligibility and preview directives.
- Prepare a wide Open Graph image for general link sharing.
- Keep a high-quality in-article image that represents the page accurately.
- Use dedicated crops when a platform preview removes important content.
- Confirm crawlers can fetch the image URL without authentication.
- Inspect cached previews with first-party debugging tools.
| Destination | Image starting point | Required verification |
|---|---|---|
| Google Discover | Relevant, high-resolution image at least 1200 px wide; Google currently recommends 16:9 | Allow a large preview and confirm crawl access; eligibility does not guarantee appearance |
| General Open Graph card | A wide 1200 × 630 px share image is a common starting frame | Validate the published metadata and fetched preview for each important service |
Reference: Google Search Central Discover guidance
The preview image is a distribution asset
A Discover or social-preview image is not only part of the page. It is part of distribution. That means the format, dimensions, and crop must work in the site delivery path and in each relevant crawler or platform. Compare WebP, JPG, and PNG for the site, then verify the downstream preview rather than assuming the same support everywhere.
The image also needs the right dimensions and crop. Format alone cannot solve a poor preview.
- WebP as one candidate for a tested site-controlled delivery path.
- JPG when the downstream preview system explicitly handles it reliably.
- PNG when lossless storage or alpha is needed and the destination accepts it.
News, tutorials, and product stories need different preview checks
A news-style card image reused on mobile-heavy traffic sources.
A tutorial preview with large overlaid text that may need a sharper export.
A branded campaign image that needs to survive both site use and social sharing.
Verify the fetched result, not only the artboard
A large source alone does not guarantee a large preview or distribution. Check crawlability, metadata, response status, image quality, page policy, and any preview directive required by current Google guidance.
Keep the subject and branding inside a generous safe area because preview crops vary. Validate the public URL and request a fresh scrape after changes; the cached card is evidence of what the platform fetched, while the editor preview is only a local expectation.
Eligibility and visual quality are separate decisions
Preview images affect click behavior, distribution quality, and page efficiency when they are reused on the site itself.
Preview image workflows should be standardized so articles do not ship random crops, formats, or dimensions.
Preview assumptions that weaken Discover or social cards
- Reusing a giant hero image without checking the preview crop.
- Ignoring mobile feed rendering when preparing the asset.
- Using a heavy format with oversized dimensions for every share image.
- Treating preview images as an afterthought instead of a distribution asset.
Frequently Asked Questions
Does a large image guarantee Google Discover traffic?
No. It can help the page meet image eligibility guidance, but Discover selection and traffic are not guaranteed.
Can one image serve both Discover and social previews?
Sometimes, but check the crop and metadata for each use. A dedicated variant may preserve the subject better.
Why does a social platform show no preview image?
Check the metadata URL, crawler access, format support, dimensions, response status, and cached scrape.
Related Tools
Sources and related reading
For Google's current Discover image eligibility guidance, consult Google Search Central Discover guidance. For a hands-on companion to Best Format for Google Discover and Social Previews, continue with Open Graph card preparation.