✨ Get 25% OFFon any plan. Use the coupon:
Automarticles
All terms

Keyword difficulty: what it is and how to assess it

By Tiago CostaUpdated on July 2, 2026

Illustration of a semicircular gauge with a needle between easy and hard, representing keyword difficulty (KD).
Definition

Keyword difficulty (KD) is the estimate of the effort to rank for a term against the competition. Tools calculate that score by looking mainly at:

  • the strength and number of backlinks of the pages already ranking;
  • the authority of the domains at the top;
  • the quality and depth of the competing content.

What keyword difficulty (KD) is

Keyword difficulty (KD) is an estimate of how hard it would be to place a page among the top Google results for a given term. It looks at who is already up there and measures the size of the obstacle.

Tools like Ahrefs, Semrush and Moz translate that contest into a score, almost always from 0 to 100. A low KD indicates that the competitors at the top are weak or that the search is lightly contested; a high KD signals very strong pages holding the first positions. Working this indicator well is a central part of keyword research, because it helps separate reachable terms from distant dreams.

Keep in mind that keyword difficulty is always relative: the same term can be easy for a strong site and hard for a new blog. The number is a reference point, not an absolute truth.

How keyword difficulty is calculated

Each tool has its own formula, but almost all start from the same main ingredient: the links of the pages already ranking. The logic is direct: if the top ten positions are held by pages with many backlinks, it will take a lot of strength to join that group.

The most common factors in the calculation are:

  • Backlinks of the top pages: how many different domains point to the results already ranking.
  • Domain authority: metrics such as Domain Rating and domain authority sum up the overall strength of the competitors.
  • Content quality: some tools also consider depth, relevance and how well the content answers the search.

No wonder links weigh so much. In a study of 11.8 million results, Backlinko found that the page in the first position has, on average, 3.8 times more backlinks than the pages in positions 2 to 10. That is why KD is, to a large extent, a snapshot of the competition's link strength.

Infographic of the factors that increase keyword difficulty: competitor backlinks, domain authority, content quality and search intent.
The factors that raise a keyword's difficulty, stacked from most decisive to complementary.

KD is not everything: intent, your site and the SERP

Relying only on the difficulty score is a classic mistake. KD is a useful summary, but it ignores context that changes everything. Three points deserve attention:

  • Search intent: the search intent behind the term defines the format that ranks. A low KD on a search that only shows stores does not help someone writing an article.
  • Your site's strength: a KD of 40 is easy for an established domain and hard for a new blog. Difficulty is always relative to who is trying.
  • What the SERP actually shows: the SERP analysis reveals nuances the score does not capture, such as weak results, forums or outdated content at the top.

The scale of the challenge also has a backdrop: in an analysis of billions of pages, Ahrefs found that 96.55% of pages get no organic traffic from Google. Most content never ranks, and choosing terms with matching difficulty is exactly what separates those who stay in that 96% from those who get traffic.

How to assess difficulty in practice (step by step)

The tool's score is the starting point, not the final decision. A simple routine to assess a term with your own eyes:

  • Search the term on Google: see who holds the top ten positions and what kind of page appears.
  • Check the competitors' authority: if the top is dominated by strong brands, the effort will be large; if there are small blogs and forums, there is an opening.
  • Analyze the content depth: read what ranks. Can you answer better, with more examples, data and clarity?
  • Look at the link profile: top pages with few backlinks are a good sign of opportunity.
  • Compare with your reality: cross all of this with your site's current strength before deciding.

This manual reading complements the number and avoids two traps: discarding an easy term just because the score looked scary, or investing months in an impossible term just because the volume was tempting.

Illustration of a scale comparing your site's page with the strong competitors at the top of the SERP, representing the assessment of keyword difficulty.

Difficulty vs volume: how to pick words worth it

The instinct to aim at very high volume terms usually comes at a high cost. They almost always bring the greatest difficulty and the heaviest competition. For most sites, the best balance lies in medium or low difficulty terms with clear intent.

This is where the long tail strategy comes in: longer, more specific searches, with less search volume, but also with lower KD and more defined intent. Winning dozens of these searches usually brings more qualified traffic than dreaming of a single, giant, unreachable term.

The practical recommendation for beginners: prioritize low KD terms to win the first positions, gain authority and only then move to more contested words. Building difficulty by difficulty is the sustainable path.

Tools to measure keyword difficulty

There are several tools to estimate KD, each with its own scale. The most used are:

ToolHow it shows difficulty
AhrefsKeyword Difficulty (KD) from 0 to 100, based mainly on the backlinks of the top pages.
SemrushKeyword Difficulty as a percentage, combining authority, links and SERP signals.
MozKeyword Difficulty from 0 to 100, tied to Moz's authority metrics.

Because the scales differ, a KD of 35 in one tool does not equal exactly a KD of 35 in another. Use the score as a reference within the same tool and always confirm with a look at the real SERP. The number guides; the results page decides.

FAQ

Frequently asked questions

What is keyword difficulty?

It is an estimate, on a 0 to 100 score, of how hard it would be to rank among the top Google results for a term, given the competition already there. The higher the number, the stronger the pages you would have to beat. It helps you choose terms with effort matching your site's strength.

Is keyword difficulty the same in every tool?

No. Each tool uses its own formula and its own scale, so the same term can have different scores in Ahrefs, Semrush and Moz. Use the score as a reference within a single tool and always confirm with an analysis of the real SERP before deciding.

What does keyword stuffing mean?

Keyword stuffing is the artificial, excessive repetition of a term in a text in an attempt to manipulate rankings. Besides hurting readability, the practice violates Google's guidelines and can drop the page instead of helping it. The focus should be on answering the search well, not on repeating the word.

What is a good difficulty for beginners?

For new sites or sites with little authority, the safest bet is to aim at low difficulty terms, generally KD 0 to 30, with clear intent. They win the first positions faster and help build authority. With a stronger site, you can gradually move to higher difficulty terms.

Does high difficulty mean high volume?

Not always, but they often go together. Very high volume terms tend to attract heavier competition and higher difficulty. That is why a strategy of medium and low difficulty terms, especially long tail ones, usually delivers more qualified traffic with far less effort.

Pick the right keywords, without guessing

Automarticles researches the keywords, assesses the difficulty and writes your blog's articles focused on the terms you can actually rank for.

Start free trial
Keep learning

Related concepts

Search volumeSearch volume is the estimated number of times a keyword is searched in a search engine, usually calculated as a monthly average. It shows the size of the demand for a term and is one of the first data points analyzed in keyword research, since it helps decide which topics are worth producing content for. Because it is an estimate, it should be read alongside difficulty and search intent, not in isolation.Keyword researchKeyword research is the process of finding, evaluating and prioritizing the terms your audience types into search engines. It combines data on search volume, difficulty and intent to decide which words are worth investing content in. It is the foundation of any SEO strategy, because it defines what to write about and in what order, aligning production with people's real questions.Long-tail keywordA long-tail keyword is a long, specific query, usually with three or more words, that has low search volume but very clear intent and a high conversion rate. Instead of fighting over generic, crowded terms, you target detailed searches like best running shoes for overpronation, which attract fewer people but people much closer to deciding. Added together, these specific searches make up most of everything searched on the internet.SERP analysisSERP analysis is the detailed study of the results page that Google returns for a keyword, done before producing content. The goal is to understand three things: the intent behind the search, the page format that already ranks at the top and the level of competition. By reading the SERP this way, you discover what the search engine has decided to reward for that term and write based on evidence, not guesswork.
See all concepts
Put it into practice

Related tools

Keyword ResearchKeywords with real Google search volume, competition and CPC.Keyword Difficulty CheckerSee, from 0 to 100, how hard it is to rank each keyword on Google.
See all tools