Keyword difficulty is an estimate, usually on a 0 to 100 scale, of how hard it will be to rank in Google’s top 10 for a keyword. It is the single most useful number in keyword research, because it stops you spending months on a term that only household names can win. This guide shows you how to check it for free, how to read the score properly, and how to compare scores when different tools disagree.
Step 1: Look at who already ranks
Before any score, look at the top 10 for the keyword in the country you sell to. A free SERP checker shows you the live UK results without the personalisation you get in your own browser. Three things tell you most of what you need:
- Who the domains are. If the top 10 is Wikipedia, GOV.UK, the BBC, Amazon and two national brands, the keyword is hard whatever a score says.
- What kind of page ranks. Homepages and category pages mean Google wants a brand or a shop. Long articles mean it wants an answer. Your page has to be the same kind of thing.
- What the SERP looks like. A Local Pack, a People Also Ask box, videos and an AI Overview all push the organic results down the page, so position 4 on a crowded SERP can be worth less than position 8 on a clean one.
Step 2: Run a free keyword difficulty checker
Our free keyword difficulty checker gives you a 0 to 100 score with no sign-up and no captcha. It reads the live top 10 for your chosen market and scores three signals, each of which you can see:
- Mega-site presence: how many of the top 10 are sites that are almost impossible to outrank.
- Title match: how many of the ranking pages have the keyword in their title. A tightly optimised SERP is harder to break into.
- URL depth: whether homepages or deep article pages are ranking. Deep pages mean the keyword is won on content, which is good news for a small site.
Here is how to read the bands:
| Score | Band | What it usually takes |
|---|---|---|
| 0 to 20 | Very easy | A well-targeted page on a site a few months old |
| 21 to 40 | Easy | A focused page with solid on-page SEO and internal links |
| 41 to 60 | Medium | A thorough page, consistent publishing and some links from other sites |
| 61 to 80 | Hard | Real authority in the topic and a page better than the current top 10 |
| 81 to 100 | Very hard | Dominated by household names. Pick a more specific keyword |
Step 3: Compare keyword difficulty across different SEO tools
Ahrefs, Semrush, Moz and the free checkers all give different numbers for the same keyword, and people often ask which one is right. None of them is. They measure different things:
- Ahrefs KD is based almost entirely on how many referring domains the top 10 pages have. It is a backlink score.
- Semrush KD blends backlink authority with search volume, SERP features and branded intent.
- Moz Difficulty uses its own Page Authority and Domain Authority plus expected click-through rate.
- SERP-signal checkers, like ours, use what is visible in the results: who ranks, how optimised the titles are and what kind of pages win.
To compare them sensibly:
- Compare bands, not numbers. A 35 in one tool and a 48 in another are both “medium” territory. Only treat a gap as meaningful when the tools land in different bands.
- Check the same country. A keyword can be easy in the UK and hard in the US. Make sure every tool is set to the market you sell in.
- Trust the backlink tools on authority and the SERP tools on intent. If Ahrefs says easy but the SERP is full of brand homepages, the SERP is telling you something the backlink count missed.
- When two tools disagree sharply, open the SERP. The top 10 is the ground truth. Our checker shows it under the score so you can see why the number came out as it did.
Step 4: Judge the keyword against your own site
A score describes the competition, not you. The same “medium” keyword is realistic for a ten-year-old site with links from the trade press and a stretch for a site registered last spring. Ask three questions:
- Does my site already rank for anything related? If Google Search Console shows impressions for neighbouring keywords, you have a foothold.
- Have I covered the topic? One page in a cluster of related pages ranks more easily than an orphan page.
- Can I make a better page than the current number one? If not, the score does not matter.
If you want this checked for you, a one-off SEO audit looks at exactly these questions for your site.
Step 5: Find easier variants
When a keyword scores hard, do not abandon the topic. Go longer and more specific:
- Use the “easier variants” the checker suggests from Google autocomplete.
- Run the topic through the People Also Ask tool and answer the questions Google already shows for it. Question keywords are often easy because few pages answer them directly.
- Add a place, a price, a comparison or a problem: “boiler service” is hard, “boiler service cost Kent” is not.
- Use the keyword suggestion tool to pull hundreds of long-tail phrases from autocomplete and score the promising ones.
How to calculate keyword difficulty by hand
If you want a sanity check without any tool, you can score a SERP yourself in two minutes. Open the top 10 for the keyword and award points:
- Up to 50 points for mega-sites. Five points for each result from a site you could never outrank (Wikipedia, government, national press, the biggest brands in the niche).
- Up to 30 points for optimised titles. Three points for each result whose title contains the keyword.
- Up to 20 points for shallow URLs. Twenty if the results are mostly homepages, ten if they are mixed, nothing if they are mostly deep articles.
Add them up and read the bands above. This is roughly what our checker does automatically, and it is a good way to understand why a tool gave the score it did.
A quick checklist
- Open the live top 10 for the keyword in your country.
- Run a free keyword difficulty check and read the band, not the exact number.
- If tools disagree, compare bands and look at the SERP itself.
- Weigh the score against your site’s age, links and topic coverage.
- If it is hard, pick a longer variant or a question and win that first.
Keyword difficulty is only one half of keyword research. For the full process, from seed keywords to a keyword map, read our guide to keyword research for UK businesses.