What is Keyword Difficulty? Everything You Need to Know

What is Keyword Difficulty (KD)?

Keyword difficulty (KD) is a metric that estimates how hard it would be to rank a page in the top 10 organic search results for a given keyword. It's expressed as a score from 0 to 100, where higher means harder.

There is no single official KD. Google doesn't publish one; each SEO tool calculates its own and labels its own ranges. Semrush, for example, publishes these bands:

• 0–14: Very easy
• 15–29: Easy
• 30–49: Possible
• 50–69: Difficult
• 70–84: Hard
• 85–100: Very hard

Because every tool measures differently, compare scores within one tool only. A KD of 30 in one tool and 30 in another don't describe the same thing.

How Each Major Tool Calculates KD

KD is primarily derived from the backlink profiles of the pages currently ranking in the top 10. If those pages each have links from many other websites, a new page with few links is unlikely to displace them. Beyond that core idea, the tools differ:

• Ahrefs bases KD on the number of referring domains (different websites linking in) that the top 10 organic results have. Its help center notes that KD does not take on-page SEO factors into account.
• Semrushuses the median number of referring domains 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 SERP-related qualities of the keyword itself”.
• Moz and other tools use formulas of their own, so expect different numbers for the same keyword.

Why the same keyword gets different scores

Put one keyword into three tools and you'll often get three different scores. That's expected, for three reasons:

• Different link data. Each tool crawls the web with its own crawler and finds a different set of links, so the same page has a different referring-domain count in each.
• Different formulas. One tool counts only referring domains; another blends in domain strength and the features on the results page.
• Different timing. Results pages change, and each tool refreshes its data on its own schedule.

None of them can see how good your page will be. KD tells you how strong the current results are, mostly in links; it can't tell you whether those pages actually answer the search well.

Keyword Difficulty vs. Google Ads Competition

These two get confused all the time, because many keyword tools show a column called “Competition” next to the volume. In many tools, RedonApp included, that column comes from Google Ads, and it measures something else entirely.

Google defines its competition index (0–100) as how competitive ad placement is for a keyword: “the number of ad slots filled divided by the total number of slots available”. It's grouped into Low, Medium and High. It tells you how many advertisers are bidding, not how strong the organic results are.

RedonApp's Competition column is the Google Ads kind.RedonApp doesn't calculate a KD score. A high Competition value is still useful, since it shows a keyword is worth money to businesses, but for organic difficulty you look at the live results, as below.

How to Judge Difficulty Without a KD Score

A KD score is a summary of the results page. You can read the results page yourself, and it tells you things no score can. Open the live top 10 for the keyword and check:

1. Who ranks. Household brands, big publishers and government sites are hard to move. Small specialist sites and personal blogs are not.
2. What type of page ranks.Tools, product pages, guides, lists or videos? Your page has to be the same type, because that's what Google has learned searchers want.
3. Whether each page matches the intent. A page that answers a different question is a weak spot, for example a spec page ranking for a search that wants a tool.
4. How deep the content is. Thin pages, outdated screenshots and pages that only half answer the question can be beaten with a better page.
5. How fresh it is. Old dates on pages about a fast-moving topic suggest an opening.
6. Forums and Q&A threads.Reddit or Quora threads in the top 10 often mean there isn't a strong dedicated page yet.
7. Links, if you can check them.A backlink checker shows how many sites link to each ranking page. RedonApp doesn't show backlink data, so use a separate tool for this step.

Our guide to finding low competition keywords lists more patterns that signal an opening.

Worked Example: Two Real Keywords

We ran two keywords through RedonApp's Keyword Research on 12 October 2026, for the United States. Both show Low Competition. Their results pages tell two very different stories.

“keyword research tool”

The live results held nine organic pages:

Verdict: hard.All nine pages were made for this exact search: five tools, three lists of tools and a video. None is a forum thread or a page answering a different question, so there's no obvious weak spot. The intent is split between “let me use a tool” and “help me choose one”, and both are already well served. A new site would need a genuinely better tool or list, plus links, before it had a chance. The Low Competition score says nothing about any of this; it only shows that ad slots for this keyword aren't all filled.

“open graph checker”

The live results held ten organic pages:

Verdict: realistic, for the right kind of page.The intent is clear: searchers want a tool, so an article won't rank here. Most results are small single-purpose tools, and two positions are held by pages that don't fully match the intent: the Open Graph specification at #8 and a browser extension at #6. That suggests the results aren't settled, and a fast, free checker that does more has a fair chance. This is the kind of results page RedonApp's own Social Preview competes on.

Note the numbers, too: Competition is 0, yet the CPC is $28.04, higher than for the first keyword. Few advertisers bid on it, but those who do bid high. Neither number tells you how hard it is to rank.

KD vs. Search Volume — What to Prioritize?

KD and volume need to be evaluated together. A keyword with KD 5 and 10 monthly searches isn't worth targeting. A keyword with KD 90 and 100,000 searches isn't realistic for most sites. The goal is to find keywords at the intersection of:

• Sufficient volume — typically 100+ searches/month to justify the effort
• Achievable difficulty— a KD you can realistically compete at given your site's current authority level

This intersection is where the best ranking opportunities live. Our guide to finding low competition keywords shows how to spot them.

KD Is a Guide, Not a Guarantee

Keyword difficulty is a probability estimate, not a rule. A high KD doesn't mean it's impossible — it means the average page will find it hard. If you produce significantly better content, earn strong backlinks, and match search intentperfectly, you can rank for keywords above your “normal” range.

Conversely, a low KD doesn't guarantee a ranking. If your content is thin or your site has technical SEO issues, even easy keywords won't convert.

Always pair KD analysis with a manual check of the results; RedonApp's keyword research toolshows the live top results for any keyword. Look at what's actually ranking — their page quality, page type and content depth — to assess whether you can realistically compete.

Common Keyword Difficulty Mistakes

• Comparing scores across tools. A 25 in one tool and a 40 in another may describe the same results page. Pick one tool and learn its scale.
• Reading Google Ads competition as KD. A Low competition value means few ads, not an easy ranking, as the first keyword above shows.
• Skipping the intent check.A low score doesn't help if every result is a tool and you plan to write an article, or the other way round.
• Chasing a KD of zero. Very low scores often come with very little search volume. Check that enough people search for the keyword to make the page worth writing.
• Treating KD as fixed. A new strong page can enter the results and change the picture. Re-check important keywords before you start writing, not months earlier.

Target KD by Site Stage

A rule of thumb from our own work, not a published standard. Use the scale of the one tool you work with, and move up a band as your site earns links and rankings.