Are your outbound links correctly marked?

Not automatically. Affiliate links, paid placements, and links inside comments or forum posts each need a specific rel attribute, and the most common way they end up wrong is not a one-time mistake, it is a link added last month that nobody went back to mark.

What Google actually asks for

Per Google's own documentation on qualifying outbound links, there are three values, and they cover different situations:

• sponsored: for links that are advertisements or paid placements. Google's guidance is direct: "Mark links that are advertisements or paid placements (commonly called paid links) with the sponsored value." The older advice was to use nofollow for these; Google now says sponsored is preferred.
• ugc: for user-generated content, comments, forum posts, anything a visitor rather than the site owner added. Google recommends marking these links with ugc, with one exception: attributes can be dropped from links by consistently high-quality contributors a site wants to reward.
• nofollow: the catch-all, for when neither of the above applies and you would rather Google not associate your site with, or crawl, the linked page.

You can combine values as a space or comma separated list when more than one applies. And per Google's own wording, links marked with these attributes "will generally not be followed," though the linked page can still be discovered other ways, through a sitemap or a link from a different site. None of these three values are mutually exclusive with a normal, unmarked editorial link either, most links on a typical site need no rel attribute at all; the attributes exist specifically for the paid, user-generated, and unendorsed cases above, not as a default to reach for.

The stakes are real, not cosmetic. Google's link-schemes policy treats an unmarked paid link that passes ranking value as a violation, which carries manual-action risk against the whole site, not just a missed best practice. Missing ugc or nofollow on a link you don't control doesn't carry that same enforcement weight, but it still means vouching, in Google's eyes, for a destination you may not actually endorse.

Why this drifts wrong over time

A site rarely gets this wrong all at once. It drifts. A new blog post ships with an affiliate link inserted by hand, and the person writing it is thinking about the content, not the rel attribute. A comment system quietly stops auto-tagging ugc after a theme update. A sponsorship deal adds three new outbound links across old and new pages, none of them marked.

None of that shows up as an error. The links work fine. Visitors click them, nothing looks broken. The only way to catch it is to go looking, and going looking on your own schedule usually means it happens once, during a big audit, and then not again until the next one.

Catching it on the next crawl instead of the next audit

WebPixie's Link Crawler lists every outbound link it finds, with anchor text, how many times each appears across your site, and the rel attributes it carries. Because this runs as part of ongoing monitoring rather than a tool you open once a quarter, a link added last week shows up in the outbound list on the next scheduled crawl, not whenever someone remembers to run an audit again.

Say a new post goes live with an affiliate link inserted manually, missing rel="sponsored" because it was typed in rather than added through a template that handles it automatically. The next crawl picks it up in the outbound link list alongside its rel attributes, or lack of one, and it is there to review before it has been live for months.

Concretely, this is the difference between a link that slips through and one that does not:

<!-- Missing the sponsored attribute -->
<a href="https://partner-example.com/product">Check out this tool</a>

<!-- Correctly marked as a paid placement -->
<a href="https://partner-example.com/product" rel="sponsored">Check out this tool</a>

The two links look identical to a visitor. The difference only matters to a crawler, which is exactly why it is the kind of thing that gets missed when review happens visually instead of by checking the markup. This is what a crawl-based outbound link list actually catches: not a broken link, but a correct-looking one carrying the wrong signal.

This is the same underlying mechanism other site crawlers use for this same check, nothing about detecting rel attributes from a crawl is unique to WebPixie. What changes is that it is already running as part of the monitoring you are doing anyway, so the check happens on a schedule you already have rather than one you have to remember to set up separately.

What to actually check

• New affiliate or sponsored content: any post with a paid or affiliate link added manually, rather than through a template, is the likeliest place for a missing sponsored attribute.
• Comment sections after a platform or theme change: a migration or update can silently break automatic ugc tagging without anyone noticing until an audit catches it.
• Links you would rather not vouch for: anything linked for reference rather than endorsement, where nofollow is the right call and default template behavior may not apply it.

None of these are one-time fixes. Each one is a category of link that keeps getting added, which is the actual argument for checking on every crawl instead of the next time someone schedules an audit. A site that treats this as a quarterly project will always be reviewing links added months ago; a site that treats it as part of monitoring catches them within a crawl cycle instead.