Nofollow is a value of the HTML rel attribute, written as rel="nofollow", that tells search engines the linking page does not endorse the target and does not want the link to pass ranking credit. In links and authority within SEO, it is the main tool for marking links that should not count as editorial votes, such as untrusted, user-generated or commercial links.
Nofollow was introduced in 2005 to fight comment spam on blogs. Since 2019, major search engines treat it as a hint rather than a directive, which means they may still use a nofollow link for discovery or ranking analysis when they consider it useful.
How nofollow works
A nofollow link is an ordinary hyperlink with an added attribute, for example a href="..." rel="nofollow". Browsers ignore the value, so visitors can click the link normally. The effect is only on search engines, which read the attribute when they process the link graph.
Under the original model, search engines excluded nofollow links from link equity calculations and did not use their anchor text as a ranking signal. Under the hint model adopted in 2019 and applied to crawling and indexing from March 2020, the search engine decides case by case whether to count, crawl or ignore the link. In practice, most nofollow links still pass little or no authority, but their target can be discovered through them.
Nofollow can be applied at the level of a single link or of a whole response, and these levels behave differently. Page-level nofollow is much broader than most site owners expect, because it covers navigation, footer and in-content links at once.
| Level | Syntax | Scope | Typical use |
|---|---|---|---|
| Link attribute | rel="nofollow" on an a element | One specific link | Untrusted or unendorsed links |
| Meta robots tag | meta name="robots" content="nofollow" | All links on the page | Pages whose links should never count |
| X-Robots-Tag header | HTTP header with nofollow | All links in the response | Non-HTML files such as PDFs |
Nofollow, sponsored and ugc compared
In 2019, nofollow was joined by two more specific values: sponsored for paid or commercial links and ugc for user-generated content. All three signal that a link is not an editorial endorsement, but they describe different reasons.
| Value | Meaning | Typical cases | Required by guidelines |
|---|---|---|---|
| nofollow | Do not associate the site with the target | Untrusted links, links not vouched for | Fallback for any unendorsed link |
| sponsored | Link exists because of payment or compensation | Advertising, affiliate, paid placements | Yes, for paid links |
| ugc | Link was added by users | Comments, forum posts, reviews | Recommended |
| No value (followed) | Editorial link that passes credit | Citations, recommendations, references | Default |
Values can be combined in one attribute, such as rel="ugc nofollow". Using nofollow for a paid link remains acceptable, because it already prevents credit from passing, but sponsored describes the relationship more precisely. A sponsored link without any qualification risks being treated as a link scheme.
Nofollow compared with other crawl and index controls
Nofollow is often misused as a way to keep pages out of search results, which it was never designed to do. It qualifies a link; it does not block crawling of the target and it does not prevent indexing.
| Control | What it does | Prevents indexing | Effect on link equity |
|---|---|---|---|
| rel=”nofollow” | Qualifies a single link | No | Usually passes little or none |
| noindex | Excludes a page from the index | Yes, once the page is crawled | Links on the page may still be followed |
| robots.txt disallow | Blocks crawling of URLs | No, URLs can be indexed without content | Blocked pages cannot pass equity onward |
| Canonical tag | Points to the preferred duplicate | Consolidates duplicates | Signals are consolidated to the canonical |
| Removing the link | Eliminates the connection | Not applicable | No credit passes at all |
If a page must stay out of the index, the correct tool is noindex, not nofollow on the links pointing to it, because other sites may link to the page without any qualification.
When to use nofollow
Nofollow belongs on links that the site cannot or does not want to vouch for. The decision is about the relationship between the linking page and the target, not about the quality of the target alone.
| Situation | Recommended value | Reason |
|---|---|---|
| Paid placement or advertisement | sponsored | Compensation must be disclosed to search engines |
| Affiliate link | sponsored | Commercial relationship |
| Link in a comment or forum post | ugc or ugc nofollow | Not reviewed by the site owner |
| Link to an untrusted source | nofollow | The site does not endorse the target |
| Editorial citation of a trusted source | No value | Genuine recommendation |
| Internal link to another own page | No value | Internal nofollow wastes discovery |
Some large publishers apply nofollow to all outbound links by default. This protects them from accidental link schemes, but it is a blunt policy that withholds legitimate credit from cited sources.
Common mistakes and misconceptions
The most persistent misconception is PageRank sculpting, the idea that nofollowing some internal links concentrates equity on the remaining ones. Search engines changed their handling around 2009, so the share assigned to a nofollow link is lost rather than redistributed.
- Nofollow links are not worthless: they can drive referral traffic, brand visibility and discovery.
- A natural backlink profile contains nofollow links; a profile with none can look unnatural.
- Nofollow on internal links hides useful pages from crawlers and should be avoided.
- Meta robots nofollow affects every link on the page and is easy to apply by accident in templates.
- Nofollow does not protect against harmful content on the target; it only describes the link.
In everyday language
A normal link is like a personal recommendation: the page is saying that the other site is worth a visit. A nofollow link is like mentioning a place without recommending it, for example when a stranger writes it on your notice board or when someone paid you to display it.
Search engines notice this difference. They give little or no credit to nofollow links, but people can still click them and reach the other site as usual.
Seen in the real world
A popular cycling blog earns income from bike shop affiliate programs and publishes sponsored reviews. It also has an active comment section where readers often post links to their own sites. An audit finds that affiliate and sponsored links pass full credit, which exposes the blog to penalties for unnatural outbound links.
The developers update the templates so that affiliate and sponsored content links receive rel="sponsored" and comment links receive rel="ugc nofollow", while editorial links to manufacturers and safety organizations stay followed. Comment spam drops because posting links no longer offers any ranking benefit, and the blog’s commercial relationships are disclosed correctly to search engines without affecting affiliate revenue.