Are Keyword Difficulty Scores Worth Trusting?

Should you trust keyword difficulty scores?

Trust them as a sorting tool, not as a verdict. Ahrefs says plainly in its own glossary that keyword difficulty is always only an estimation, because Google does not disclose all its ranking factors. The number is a useful way to order a long list. It is a poor way to decide what to write.

Every SEO tool ships one of these scores, and every marketing team we work with has at some point planned a quarter around them. The scores feel objective because they are numbers. Underneath, they are mostly one input dressed up as a forecast.

So this piece is about what the number is actually made of, where it holds up, and what we look at instead when the stakes are high.

How is keyword difficulty actually calculated?

Mostly from links. Ahrefs describes its method directly: it pulls the top 10 ranking pages for a keyword, counts how many websites link to each, and plots the result on a logarithmic scale from 0 to 100. More links to the current winners means a higher score.

Ahrefs is open about why the method is so narrow. Its glossary says the company intentionally keeps the calculation simple because backlinks are probably the only easily measurable confirmed ranking factor. That is an unusually honest sentence from a tool vendor, and it tells you what you are buying.

Semrush builds a wider formula. Its knowledge base says the score uses the median number of referring domains pointing to the ranking URLs, the median ratio of dofollow to nofollow links pointing to them, the median authority score of the ranking domains, and the search result qualities of the keyword itself. It reports the result as a percentage from 0 to 100.

Why do two tools give the same keyword different scores?

Because they are measuring different things and calling them the same thing. One method counts linking websites to the top 10 and curves the result. Another blends referring domains, link ratios, domain authority, and search feature data. Different inputs produce different numbers from identical search results.

The scales differ too, even when both run 0 to 100. Ahrefs says its scale is logarithmic, which means the gap between 30 and 40 is not the same amount of work as the gap between 70 and 80. Semrush publishes named bands instead: 0 to 14 is very easy, 15 to 29 easy, 30 to 49 possible, 50 to 69 difficult, 70 to 84 hard, and 85 to 100 very hard.

This matters in practice. A keyword scoring 35 in one tool and 55 in another has not changed. Your reading of it has. If your content plan has a cutoff at 40, which tool you bought just decided your roadmap.

What does keyword difficulty leave out?

Almost everything about you. The score describes the pages currently ranking. It knows nothing about your site, your topical depth, your brand recognition, or whether you have a real product behind the page. Two companies looking at the same score face completely different jobs.

It also knows very little about intent. A query where the top results are all documentation pages and a query where they are all product pages can score identically. The link counts look similar. The chance that your blog post displaces either one is not similar at all.

And it cannot see Google's actual system. Google's own guide to its ranking systems says it uses automated ranking systems that look at many factors and signals about hundreds of billions of web pages, working at the page level. No published score reconstructs that from the outside, and no vendor claims to.

When is a difficulty score genuinely useful?

When the list is too long to read. Ahrefs says it directly: keyword difficulty is a handy metric when you work with large keyword lists. If you have exported four thousand queries, a rough score is a reasonable first filter to get you down to a few hundred worth looking at.

It is also useful as a sanity check on ambition. If every keyword in your plan sits in the 70 to 100 range and your site is eight months old, the score has told you something true about sequencing, even if it is wrong about any single query.

We find it most honest when used as a relative comparison inside one tool, on one date, for one market. Keyword A scores lower than keyword B in the same export. That comparison carries information. The absolute number does not carry much.

When does a difficulty score mislead you?

When the search results are not what the score assumes. Plenty of queries are dominated by forums, review sites, or a single reference page with enormous link equity. The score reads that as hard. It may actually be impossible for a vendor page, or surprisingly open if the intent is unserved.

Low scores mislead more often than high ones. A keyword with almost no links to the top results and a difficulty of 4 usually means nobody has bothered, which sometimes means there is no demand and sometimes means the query is a navigational dead end. Our piece on targeting keywords with no search volume deals with the other side of that trap.

The worst failure is using the score to decide quality. A difficult keyword is not a signal to write more words, and an easy one is not permission to write less. The content still has to be the best answer on the page, which is a judgement no score makes.

What should you look at instead of the score?

The search results themselves. Ahrefs' own advice is that manual analysis of the search results will be more informative than the metric if you want to properly gauge your chances of ranking for a particular keyword. That advice costs a few minutes per keyword and beats the number almost every time.

When we look at a result page, we are asking three things. What kind of page is winning, who is publishing it, and is there an angle nobody has covered. A page type you cannot credibly produce is a stop sign regardless of difficulty. A gap in the coverage is a green light regardless of difficulty.

The second input is your own position. A site with real topical depth in one area can take queries that score as hard, and will struggle with easy ones outside its lane. Our notes on competitor analysis in search cover how to work out which lane you are actually in.

How do you use your own Search Console data to judge difficulty?

By looking at where you already appear. Google's documentation for the Search Console Performance report lists clicks, impressions, click-through rate, and average position, with average position in the chart being the average position of the topmost result from your entire site. That is real data about you, not an estimate about strangers.

The queries where you sit at position 11 to 20 with meaningful impressions are the best difficulty signal you will ever get. Google has already decided you are relevant enough to show. The gap between there and the first page is usually smaller than any tool score suggests.

Google notes that the default view of the report shows the past three months, so set your window deliberately when you compare periods. A plan built from your own impression data is grounded in a way a keyword export never is. Our Search Console guide walks through which reports actually drive decisions.

Does keyword difficulty mean anything for AI search?

Very little, as far as we can tell. Difficulty scores are built from link counts to the top 10 blue links. An answer engine that synthesises a response from several sources is not running that auction, so a score derived from it does not transfer cleanly to whether you get cited.

We would not claim to know how any specific answer engine weights sources, and anyone telling you they do is guessing. What we can say is that the inputs differ. Being quotable, specific, and clearly attributed looks more relevant to citation than having more referring domains than the current number one.

That makes keyword difficulty a narrowing metric over time rather than a broken one. It still describes the classic search auction. It just describes a smaller share of how people find answers than it did three years ago.

How do we use these scores in our own work?

As a first pass and nothing more. We use them to cut a large export down to a reviewable list, then we throw the number away and look at the search results. The decision about what to publish comes from the result page and the client's actual authority, not from a column in a spreadsheet.

We also try to keep the scores out of client reporting. A difficulty average is not a result, and reporting it tends to create arguments about the tool rather than about the work. Impressions, positions, and what moved after a change are harder to argue with.

Where we are blunt with clients: if a plan depends on difficulty scores being accurate, the plan is fragile. Vendors say so themselves. Building on a number its own publisher calls an estimation is a choice, and it should be a conscious one. Our view on how long SEO actually takes comes from the same place.

What will keyword difficulty mean a year from now?

Less, and more honestly labelled. The scores are getting better at explaining what they measure, which is progress, and worse as a proxy for the whole job, because the whole job now includes being retrievable by systems that do not count links the same way. Expect the number to stay useful and shrink in importance.

The teams that handle this well will be the ones who already treat the score as a filter. They will add their own impression data, their own result page reading, and a clear view of what they can credibly be the best answer for. That mix does not go stale when a vendor updates a formula.

If you are staring at a keyword plan and trying to work out which numbers to believe, we are happy to go through it with you and say what we would actually chase. Find us at phoenix.studio.