Keyword difficulty, explained

Keyword difficulty (KD) is the number most people use to decide whether a keyword is worth chasing. It is useful, but only if you know what it measures and what it leaves out.

What keyword difficulty measures

Keyword difficulty is a 0–100 estimate of how hard it is to reach the first page of Google for a keyword. Every major tool calculates it a little differently, but they all lean on the same idea: look at the pages already in the top 10 and measure how strong their backlink profiles are. If the top 10 is full of pages with links from thousands of strong sites, the keyword is hard. If it is full of pages with few links, it is easier.

The KD we show comes from DataForSEO Labs and follows that approach. A higher number means harder.

Why every tool shows a different number

You can look up the same keyword in three tools and get 23, 41 and 58. None of them is wrong. They differ because:

• Each tool has its own link index. Different crawlers find different links, at different times.
• Each tool has its own formula. Some weight referring domains, some weight authority scores, some add other signals.
• Each tool has its own scale. A 40 in one tool is not a 40 in another.

So compare keywords inside one tool, never across tools. KD is a ranking of keywords against each other, not an absolute measure. More on this on our metrics page.

What keyword difficulty does not tell you

KD is built mostly from links. It ignores several things that decide who ranks:

• Search intent. If Google shows product pages and you have a blog post, KD is irrelevant: you are not eligible. Check the results page.
• Topical authority. A site that has covered a topic in depth often outranks sites with more links. A KD of 50 can be easy for a specialist site and impossible for a generalist.
• Content quality and freshness. For queries where results change often (news, “best X in 2026”), a better, fresher page can break in with fewer links.
• SERP features. A low-KD keyword can still send few clicks if an AI Overview and a featured snippet answer it at the top.

How to use KD well

1. Know your own strength

Look at your site’s Authority Score and the KD of keywords you already rank for in the top 10. That is your real ceiling. A site whose top-10 keywords mostly have KD under 30 should not build a content plan around keywords at 60+.

2. Shortlist by intent, then KD

Filter your keyword ideas to the intent you can serve, then sort by KD. Among keywords with similar volume and the right intent, start with the lowest difficulty.

3. Check the results page for every keyword you commit to

Open the SERP overview and look at:

• Who ranks: big brands, forums, small sites like yours? Reddit, Quora or small blogs in the top 10 are a sign of an opening.
• Page types: guides, product pages, tools, videos? Match the format.
• Freshness: how old are the ranking pages? Old pages invite a better, current one.

4. Balance the plan

A good content plan mixes:

• Low-difficulty keywords that can rank within weeks and build topical authority.
• Medium-difficulty keywords that are the commercial core.
• A few high-difficulty head terms you build towards over months, supported by internal links from the easier pages.

Keyword difficulty and links

Because KD is mostly about links, it also tells you roughly how much link building a keyword needs. If the top 10 pages each have links from dozens of sites, plan for outreach: a backlink gap analysis against those pages is the fastest way to find realistic targets.

A worked example

You run a small SEO consultancy and look at three keywords:

“seo audit” looks attractive on volume, but the KD is high and the results are mostly tools, a format a consultancy cannot match. “seo audit for small business” has the lowest volume, but it matches what you sell and has low difficulty: that is the page to write first. The checklist is a strong supporting article that can link to it.

Try it: our keyword research shows volume, KD, CPC and intent for 42 countries, with matching terms, questions and a SERP overview, and sends your shortlist straight to the rank tracker.