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Searchpedia SEO field notes Callum Bennett Callum

Tool lab

Keyword Checker

I used to think keyword checkers were for finding new terms, but I've learned they're better at validating what you already suspect.

Intermediate5 min readUpdated 2026-07-27Notes by Callum Bennett

The short verdict

  • Start by checking the SERP yourself before trusting any difficulty score — the tool's algorithm doesn't see intent.
  • Use a keyword checker to audit your existing pages for on‑page targeting gaps, not just to generate new ideas.
  • Cross‑reference volume data with your own analytics to avoid chasing vanity metrics that never convert.
  • If you optimise for a keyword the tool says is easy but the top results are all big brands, you are wasting time.

What it's good at

A keyword checker is best at validation, not discovery. I used to run a seed term through a tool and chase the 100 long‑tail suggestions it spat out. Now I start with a page I already have, plug the target keyword into the checker, and see whether the title tag, H1, and meta description actually mention it. That instant audit saves hours. For example, I recently checked a client's product page for "organic coffee beans" — the tool showed the keyword was absent from the H1 and present only in a weak image alt. One edit later, the page moved from position 18 to 9 in six weeks.

Volume estimation is another strength, but only if you treat it as a range. I saw a query with a reported 1,200 monthly searches in [Ahrefs](/ahrefs/) and 780 in [Semrush](/semrush/). The truth is somewhere in between, but both numbers told me the term had enough traffic to justify a dedicated page. Without that cross‑reference, I might have ignored it.

Keyword difficulty scores are useful when you normalise them against your own site's authority. A page with a domain authority of 30 should not trust a difficulty score of 40 if the top 10 results all sit at 70+. The tool cannot know your specific situation. I use the score as a rough filter: anything below 50 gets a manual look at the SERP. That check has saved me from chasing terms that look easy on paper but are dominated by Wikipedia and Amazon.

What it's awkward for

I have been misled by keyword checkers more times than I like to admit. The biggest mistake was trusting a difficulty score of 15 for a local query like "plumber Brighton". The tool saw low backlink counts on the top results, but it missed that every result was a Google Business Profile with hundreds of reviews. My page never broke into the local pack. The tool cannot model local intent or the prominence signals Google uses for maps.

Another awkwardness: keyword checkers that claim to analyse on‑page optimisation often miss the substance of the content. I ran a page through a checker that said it was 90% optimised for "best running shoes". The title and H1 were fine, but the body was a thin list of five products with no buying guide. The tool did not penalise the lack of depth. A human reading the SERP would see that the top results were 2,000‑word comparison articles. The checker gave me false confidence.

Brand keywords are another blind spot. Search for your own brand name in a keyword checker and it will likely show zero volume or high difficulty, because the tool's data is aggregated across devices and locations. I once abandoned a perfectly good brand term because the tool said it had 10 searches a month. My analytics showed 200 visits from people searching my brand directly. The tool simply missed the long tail of branded queries.

Finally, rank‑tracking keyword checkers are awkward for any query where the SERP is personalised or features local results. They show you a static position, but your real position depends on the searcher's location, history, and device. I stopped using the rank check function and now rely on [Search Console](/serp-checker/) filtered by query and country.

Alternatives I'd consider

If I need to validate on‑page optimisation without the noise of a full keyword tool, I use [Surfer SEO](/surferseo/). It compares your content against the top‑ranking pages and gives specific recommendations for word count, heading structure, and term frequency. I ran a blog post about "vegan protein powder" through Surfer and it told me I was missing a table comparing brands. I added it, and the page climbed from 14 to 6 in two months. No keyword checker I've used gives that level of content guidance.

When budget is tight, [Ubersuggest](/ubersuggest/) is a decent free alternative for volume and difficulty estimates. Its data is not as fresh as Ahrefs or Semrush, but it is good enough for early‑stage research. I pair it with [Keywords Everywhere](/keywords-everywhere/) to see monthly search volume and cost‑per‑click data directly in the SERP without leaving Google. That combination costs less than a tenner and covers most of my needs.

For a tool that tries to do everything—keyword research, rank tracking, competitor analysis—I look at [SE Ranking](/se-ranking/). It is less known than the big two, but its keyword suggestion tool surfaces long‑tail queries that Ahrefs and Semrush sometimes miss. I used it for a niche outdoor gear site and found 30 terms with decent volume and low difficulty that the other tools had not listed.

My rule: no tool replaces sitting in the SERP yourself. I open the top 10 results, read the page titles, check the featured snippets, and ask myself: "What intent is everyone serving here?" If the keyword checker says "informational" but the SERP is full of product pages, I trust the SERP. That practice has saved me from optimising for the wrong query more often than any tool.

Next step

Quick answers

Can a keyword checker tell me if a keyword is worth targeting?

It can give you volume and difficulty estimates, but that is not enough. You also need to check search intent, your site's authority, and the competitiveness of the top results. A tool that says 'easy' may still be hard if the SERP is packed with big brands or local results.

How accurate is keyword difficulty?

Not very, on its own. Each tool uses a different algorithm—some look at backlinks, others at domain authority, and a few at content quality. Two tools can give you a score of 20 and 60 for the same keyword. Use difficulty as a rough filter, then manually inspect the SERP.

Should I use a free keyword checker or pay for one?

Free tools like Ubersuggest or the Google Keyword Planner are fine for starting out, but they lack depth. Paid tools like Ahrefs or Semrush provide more accurate volume data, competitor analysis, and on‑page audits. If you are serious about SEO, invest in one paid tool and cross‑reference with a free one.

Sources

Primary documentation is linked directly. Anything commercial is marked nofollow.

Notes from Callum Bennett.