Google clarified its favicon documentation on 28 August 2026: the current Google Search Central guide now explicitly lists seven favicon file formats: BMP, GIF, ICO, PNG, JPEG, PPM and TIFF. Google’s documentation update log says the supported formats did not change, so this is not evidence of a new ranking signal or a change in how favicons are selected.
Short answer: publish one stable, square, crawlable favicon URL for each hostname, reference it with a valid <link rel="icon"> element, use one of Google’s listed formats, and allow days to weeks for recrawling. Google does not guarantee that a favicon will appear in Search. Validate the HTML, the image response, crawler access and the hostname boundary before treating the change as complete.
This focused evergreen guide is prompted by Google’s 28 August 2026 documentation update. The official page says the formats supported by Google Search are BMP, GIF, ICO, PNG, JPEG, PPM and TIFF. A 28 August Search Engine Roundtable report provides supporting context on the earlier ambiguity, but Google’s own pages remain the source for the implementation rules.
What Google’s favicon update actually changes
The practical change is certainty in the documentation. Google now presents a finite list instead of sending site owners to a reference that could evolve. The list is a documentation boundary, not a promise of display, indexing or improved rankings.
| Question | Documented answer | What a marketer should do |
|---|---|---|
| Which formats are listed? | BMP, GIF, ICO, PNG, JPEG, PPM and TIFF | Use one listed, pixel-based asset and test the actual URL. |
| Does Google promise a favicon in results? | No. The favicon can be included; display is not guaranteed. | Do not report a Search appearance as a guaranteed outcome. |
| Is this a ranking update? | The documentation update does not establish a ranking effect. | Measure brand recognition or troubleshooting outcomes separately from rankings. |
| How many can a hostname define? | Google documents one favicon per hostname. | Use the correct host, including the correct subdomain. |
For the surrounding crawl, rendering and indexability checks, use the technical SEO guide. A favicon fix is a small asset change, but it still depends on a page that can be crawled and a URL that remains stable.
The seven formats in the current Google Search documentation
- BMP
- GIF
- ICO
- PNG
- JPEG
- PPM
- TIFF
The page does not list SVG in this seven-format sentence. That is a reason to provide a listed fallback when a site currently relies on an SVG-only favicon, not a reason to claim that every SVG implementation has been tested or that Google has announced a new SVG policy. Check the current Google page and the response from your own favicon URL before changing a production asset.
Implement the favicon with a stable HTML reference
Google’s example uses a link element in the document head:
<link rel="icon" href="/path/to/favicon.ico">The documentation says the rel value can be icon, shortcut icon, apple-touch-icon or apple-touch-icon-precomposed. The href can be a relative or absolute URL, including a CDN URL. For a simple Search implementation, keep one canonical, stable URL, use rel="icon", and make sure the URL serves the intended asset without an accidental redirect chain or access rule.
Do not confuse a browser tab icon with an advertising logo. Google’s favicon guidance concerns organic Search results; advertising logos have their own product and asset requirements. If a campaign brief says “update the logo,” confirm which surface is in scope before editing a site-wide head template.
Google’s technical requirements and boundaries
One favicon per hostname
Google documents one favicon for each hostname. A domain and a subdomain can have different favicons because they are different hostnames. A subdirectory cannot establish a separate Search favicon for the same hostname. Decide whether the relevant host is, for example, example.com, www.example.com or a product subdomain, and test that host rather than assuming the root-domain asset controls every deployment.
Make the asset crawlable
Google’s guidance says Googlebot and Googlebot-Image need access to the favicon and its page context. Check that robots rules, authentication, firewall policy, CDN hotlink protection and response headers do not block the asset. A successful browser load from an employee network is not proof that Googlebot can fetch it.
Use a square, representative image
The documented minimum is 8×8 pixels, while Google recommends an image larger than 48×48 pixels. The image should be square, representative of the site or brand, and not an inappropriate or misleading image. Larger source artwork can be exported to a practical pixel format while preserving legibility at the small display size.
Keep the URL stable
Google recommends a stable favicon URL. Do not rotate the file path on every campaign, attach an expiring signed URL, or make a theme deployment silently point to a different asset without recording the change. If a rebrand requires a new image, change the asset deliberately, keep the reference valid and record the date so a later Search observation is not mistaken for a crawl failure.
Allow time for recrawling
Google says it may take days to weeks to recrawl and update the favicon. The documentation also points to URL Inspection as a way to request indexing. A request is a crawl signal, not an SLA. Avoid repeated file swaps or emergency ticket escalation during the normal recrawl interval unless logs show a real access or response problem.
If the crawler appears not to revisit the page or asset, compare the result with the Google crawl-budget update guide. The favicon change itself does not create a license to make broad crawl-budget changes.
A practical favicon QA checklist
Run the checks below for every hostname that has its own brand surface. The first group verifies the documented implementation; the second group is an operating recommendation for a reviewable SEO change.
| Check | Pass condition | Evidence to retain |
|---|---|---|
| Format | Asset is BMP, GIF, ICO, PNG, JPEG, PPM or TIFF. | File name, response headers and a copy of the asset. |
| Shape and size | Square; at least 8×8 pixels; preferably larger than 48×48. | Image dimensions and a small-size visual check. |
| HTML reference | Head contains a valid favicon link with the intended URL. | Rendered HTML or page-source capture. |
| Hostname | Test is performed on the exact hostname that should show the icon. | Canonical URL and host list. |
| Crawler access | Robots, authentication, CDN and firewall rules allow Googlebot and Googlebot-Image. | Robots review, response code and access-log evidence where available. |
| Stability | URL is durable and does not depend on an expiring token or campaign parameter. | URL, redirect result and cache/CDN policy. |
| Search expectation | Team understands that display is not guaranteed and may take days to weeks. | Change receipt with the observation date. |
Pair the asset review with the on-page optimization checklist so the change is not evaluated in isolation from title, canonical and rendered-page checks.
WordPress and CDN checks for marketers
Most marketers will not edit a theme file directly, so the safest workflow is to give the developer or platform owner an exact asset contract:
- Name the hostname and the pages or templates affected.
- Attach the approved square asset and state its file format and dimensions.
- Specify the intended stable URL and the exact
link rel="icon"reference. - Ask for a rendered head check on the canonical page, not just a CMS media-library confirmation.
- Ask the owner to verify the asset as an anonymous request and against the site’s crawler policy.
- Record the deploy time, old URL, new URL, response code, redirect behavior and reviewer.
- Request indexing once the implementation is correct, then set a reasonable observation date rather than promising a Search result.
For a broader technical diagnosis, run the site SEO audit checklist. Do not change robots rules, CDN policy, canonical tags or theme templates merely because the favicon is not visible immediately; first identify whether the problem is format, HTML reference, hostname, access, crawl timing or the documented lack of a display guarantee.
Use the Google Search Console platform-properties guide when checking the exact host and property. If the request starts to expand into a broader page or query rewrite, return to the search-intent guide and keep the favicon task narrowly scoped.
What this update does not prove
- It does not prove a ranking boost. A favicon can improve recognition when it appears, but the current guidance does not establish a ranking signal or traffic uplift.
- It does not make every image format interchangeable. Use the formats listed by Google Search and validate the actual response.
- It does not guarantee a visual result. Google may not display the favicon, and recrawling can take days to weeks.
- It does not make SVG a confirmed Search format. SVG is absent from the current seven-format list; provide a listed fallback if the site depends on SVG alone.
- It does not define advertising logos. Organic Search favicon guidance and ad-asset requirements are separate concerns.
- It does not justify a broad site migration. Fix the relevant asset and host boundary first; preserve the rest of the site’s URLs and metadata.
FAQ
Is ICO the only safe favicon format for Google?
No. Google’s current Search documentation lists BMP, GIF, ICO, PNG, JPEG, PPM and TIFF. ICO is one listed option, not the only one. The implementation still needs a square, crawlable, representative asset at a stable URL.
How large should a favicon be?
Google documents a minimum of 8×8 pixels and recommends an image larger than 48×48 pixels. Use a square source that remains recognisable at the size used by the browser or Search interface.
Can a subdirectory have its own Google favicon?
Google documents one favicon per hostname. A subdomain is a separate hostname; a subdirectory is not. A subdirectory therefore should not be treated as an independent Search favicon owner.
How long will a favicon change take to appear?
Google says recrawling can take days to weeks and does not guarantee display. Request indexing after the implementation is correct, then monitor the relevant host and asset without treating the request as a guaranteed deadline.
Should a favicon change be reported as an SEO win?
Report the implementation and Search appearance separately. The documentation clarifies formats and requirements, but it does not supply a ranking, click-through or revenue estimate. If brand recognition matters, define a separate measurement plan rather than inventing a performance claim.
For date-sensitive changes, log the exact source date and observation date in the Google algorithm-updates log. For the content and navigation around a technical fix, use the internal-linking strategy guide to keep supporting pages clear and contextual.
Bottom line
Google’s 28 August 2026 favicon documentation update makes the supported Search formats explicit: BMP, GIF, ICO, PNG, JPEG, PPM and TIFF. The useful action is a narrow QA pass: choose a listed square asset, reference it at a stable URL for the correct hostname, allow Googlebot and Googlebot-Image to crawl it, request indexing after the implementation is sound, and wait through the documented recrawl window. Treat the favicon as a Search appearance and brand-recognition detail, not as a promised ranking lever.
