Not all links are the same, and pretending they are is how sites get themselves in trouble. Some links earn you real trust. Most do nothing at all. And a few will earn you a penalty if you collect enough of them.

This is the full field guide: twenty-five kinds of backlink, what each one is, what Google has actually said about it, and the plain verdict on whether it is worth your time. To make it useful rather than exhausting, they are sorted into three piles. The ones worth earning, the ones that are fine but were never a strategy, and the ones to leave well alone.

One thread runs through all of it. The links that help are the ones you earn by being useful and building real relationships. The links that hurt are the ones you manufacture. Keep that in mind and most of the twenty-five sort themselves.

These are the links Google actually wants, the ones that exist because a real person chose to point at you. They are also the hardest to get, which is rather the point.

A link inside a piece of content, placed by the writer because your page genuinely supports theirs. This is the gold standard, and Google says so plainly: links that are not editorially placed or vouched for are the ones it treats as unnatural. You cannot buy these without turning them into something else. You earn them by making things worth citing, which is the whole of how to get backlinks worth having.

Guest post links

A post you write for another site in your field, with a credit back to yours. Google is fine with guest posts that genuinely inform an audience, and against them when the point is links at scale. Matt Cutts called the decay of guest blogging for SEO in January 2014, then updated the post to clarify he meant the spammy, industrial version. Write something you would be proud of, for a site you would actually read, and let the link be a credit rather than the reason.

Resource page links

A spot on a page that curates the best resources on a topic. Genuinely useful when the page is real, gets traffic, and lists quality work alongside you. Worth pursuing when the fit is honest and the list is one you would be glad to appear on.

Reviews and testimonials

A testimonial you write that a partner publishes with a link, or a review someone does of you. Fine in moderation. The moment you hand out free product in exchange for the link, Google treats it as a scheme. A few real ones, given because you mean them, are a positive. A strategy built on them is not.

Infographics

A well-designed visual of real data, shared with an embed. Still valuable when the data is accurate and the embed does not force a keyword-stuffed link. Google has warned it may discount these. Matt Cutts’ reasoning was that “the link is often embedded in the infographic in a way that people don’t realize, vs. a true endorsement of your site”. That was 2012 and it has aged well, so let the graphic earn its shares on merit.

Press releases, when genuinely newsworthy

The industry line is that press release links count as advertising and must all be nofollowed. Google’s actual wording is narrower than that. Its link spam policy names “links with optimized anchor text in articles, guest posts, or press releases distributed on other sites”, so what it objects to is the keyword-stuffed anchor sprayed across a wire, not a link existing in a release. A release still earns real coverage when you have something actually newsworthy, and the value is the journalist who picks it up and writes about you, not the wire link itself. If it is not news, skip it.

This is the biggest pile, and the honest one. These links are not against the rules in moderation, but most carry little or no ranking weight. Do them for real reasons, community, visibility, a better experience for a reader, and treat any link as a side effect rather than the goal. Brand or plain-URL anchors, nofollow where the link is not really an endorsement, and never at industrial scale.

A link from the author profile on articles you publish. Low value, and Google finds and discounts bio links easily. If you use one, make it your brand or your URL, not keyword-stuffed anchor text.

Nofollowed since 2005, which is exactly what that change was for. Commenting on relevant, high-quality sites can build your reputation and send traffic. Do it to be useful, with your real name, never automated, and never for the link.

Same story as blog comments. Genuine participation in a community is valuable, which is why most forums nofollow the links. Before you drop one, ask whether it helps the people reading or just you.

A sidebar list of sites the owner likes, usually sitewide. A few natural ones are fine. Bought in bulk, they were hit hard by Google’s updates. Keep the anchor to your brand and the linking site genuinely relevant.

Sitewide footer links carry little weight, and keyword-rich ones were an old paid-link trick. Google’s link spam policy names “widely distributed links in the footers or templates of various sites”, so scale is what turns this from harmless to a problem. There are legitimate reasons to link in a footer, a related company site, for instance. Use brand anchors, nofollow where the link is not a real endorsement, and do it for users, not rankings.

A link on every page of a site. Limited value at best, and a negative signal when it looks systematic or bought. A few legitimate cases exist, but it is not something to chase.

The link field on a social account. Not worth much as a link, and Google largely ignores them. Social profiles matter for visibility and network, which is where the real value is, so build the presence, not the link.

Social media post links

Links you post to your own site from social platforms, typically nofollow and treated as user-generated content. Not a direct ranking factor. They drive reach and traffic and can lead to real links, which is a different and worthwhile game. Just do not be spammy.

An old tactic, and a dead one. Google does not merely ignore these, it names “low-quality directory or bookmark site links” in the link spam policy outright, which puts the industrial version closer to the third pile than this one. Your time is better spent genuinely taking part in the communities your audience actually uses, where real sharing and links can follow.

User profile page links

The profile link many sites hand you when you sign up. A few, on sites you actually use, are fine and can send traffic. Creating hundreds of profiles for the links is a waste of time with no real benefit.

Once a boost, now mostly not, and Google’s link spam policy names “low-quality directory or bookmark site links” directly. It is not that every directory is bad, it is that most are, so the skill is telling a genuinely useful, relevant listing from the rest. Get it wrong at volume and you are inside the policy rather than in the grey area beside it.

A 301 redirect legitimately passes authority between domains, and it is a real tool when you are moving or consolidating sites you own. Building spammy links to a throwaway domain and redirecting it to your main site is just spam with an extra step. John Mueller put it bluntly: “you might as well skip the detour, it’s just as obvious to the algorithms & spam team.” Google has since gone further and named expired domain abuse as a spam policy in its own right. Use redirects for real reasons only.

Two sites agreeing to link to each other. An occasional relevant swap is normal and harmless. Doing it excessively, or on “partners” pages built only for cross-linking, is a scheme in Google’s own words. Where exactly the line sits is worth its own read: are link exchanges safe?

These are either straight violations of Google’s guidelines or a pure waste of your time. No clever version makes them safe.

Article directory links

Submit-and-syndicate content farms. Matt Cutts told people to stay away in 2014, on the grounds that the content “tends to be a little bit of lower quality stuff” that gets “sprayed and syndicated all over the entire web”, and nothing has improved since. They will not help, and enough of them will hurt. Do not waste your time.

Links spun out by automated tools across comments, forums and wikis. Google names “using automated programs or services to create links” as a link scheme outright. There is no right way to do this one.

Keyword-rich links in a forum signature, built purely for SEO. Google’s link spam policy names “forum comments with optimized links in the post or signature” specifically. If you are in a forum for real reasons, a nofollowed brand link is the most you would ever want, and even that is not for link building.

Money, or free product, in exchange for a link that passes ranking value. Google has been clear and consistent that this is a scheme, and getting caught means a penalty. Spend the budget on something worth linking to instead.

A network of sites you control, built to link to your money site. It is against Google’s guidelines, full stop, and the whole game is hiding a footprint you can never fully hide. A clear black-hat move with a clear downside.

A link embedded in a widget you distribute, placed on sites that never really chose it. Google’s policy names “keyword-rich, hidden, or low-quality links embedded in widgets that are distributed across various sites”. If you ship a widget, any link in it should be nofollowed and a brand term, and never the point of the exercise.

The pattern underneath all twenty-five

Read the three piles and the rule is obvious. The links worth having are the ones a real person chose to give you, because you were worth citing or worth partnering with. The links to avoid are the ones you manufactured to fool a machine. Everything in the middle is fine in small, human doses and pointless in bulk.

That has always been true, and it is becoming more so. As search shifts toward AI answers, being genuinely talked about, mentioned and recommended across trusted places, is starting to matter alongside the links themselves. Brand mentions vs backlinks gets into that. The through-line does not move: real reputation, earned from real relationships, is the thing that lasts. It is the same thing value for value has always built.

Frequently asked questions

What are the different types of backlinks? Broadly, editorial and contextual links (the ones worth earning), a long middle of low-value links that are fine in moderation (social, forum, directory, profile, footer, and so on), and a set to avoid (paid links, PBNs, article directories, automated links). This guide covers 25 of them.

Which backlinks are best for SEO? Editorial and contextual links from relevant, trusted sites, the kind a writer chose to include because your page was worth citing. They are the hardest to get and the most durable, and they come from being genuinely useful and building real relationships.

Which backlinks are bad or risky? Paid links, private blog networks, article directories, automatically generated links and forum-signature spam are all against Google’s guidelines and can earn a penalty. Most other low-value types are a waste of time rather than dangerous.

Do nofollow links help SEO? Not as a direct ranking vote, though the rule is softer than it used to be. In March 2020 Google began treating nofollow as a hint rather than a strict instruction, alongside the newer rel=“sponsored” and rel=“ugc” attributes, so it may or may not count one. In practice most nofollowed links still pass nothing. They can still send referral traffic, build visibility, and lead to real editorial links later, so they are worth having for reasons other than passing ranking value.

Are reciprocal or link-exchange links safe? An occasional relevant swap is normal. Doing it systematically, or on pages built only to cross-link, is a scheme in Google’s own words. The full nuance is in the honest take on link exchanges.

The short version

A handful of link types are worth earning, most are fine only in small human doses, and a few will get you penalised. The good ones all have the same root: a real person chose to point at you because you were worth it.

Which comes back to relationships, and to the boring problem of finding the right sites to build them with. That is what Engado is for. It surfaces relevant, verified businesses in your niche, so you can find the people worth earning a link, a mention, or a partnership from, and start a real conversation. (The surfacing runs overnight on a batch job we named Gerald. Gerald asks for nothing and judges no one.) Earn the links worth having. Skip the rest.