Free Keyword Gap Tool: Keywords Your Competitor Ranks For

What is a keyword gap tool?

A keyword gap tool compares your website with a rival's website in Google search. It lists the keywords where the rival ranks well and your site doesn't rank at all. Each keyword shows its monthly search volume, its difficulty, its search intent and the rival page that ranks. You end up with a short list of topics your site is missing.

That list matters because your rival has already done the hard test for you. Their page ranks, so Google thinks the topic fits a site like theirs. People search for it every month. And right now, every one of those searchers lands on a rival page and never sees yours.

Most keyword research starts from a blank page. You guess at topics, check the volume and hope Google agrees. A gap check starts from proof. The keywords on the list already send traffic to a business that sells what you sell. Your job is to decide which ones fit your site and then build a better page.

A gap check also keeps you honest. Most teams think they cover their market well. Then they run a gap check and find a whole set of buyer questions they never answered. Some of those questions are small. Some of them are the reason a rival gets the demo requests you don't.

This free tool gives you the top 20 gap keywords for one rival in one country. It also tells you the total size of the gap, so you know whether you're missing 30 keywords or 3,000.

How to use the keyword gap tool

You need 2 domains and a country. The check takes under a minute.

Enter your domain. Type the root domain, like yoursite.com. You can leave out https:// and www. The tool cleans the address before it runs.
Enter a rival's domain. Pick a site that competes with you in Google for the same buyers. This may differ from your sales rival. A blog or a marketplace can take more of your search traffic than the company you meet in deals. The 2 domains must be different.
Pick a country. Rankings and search volume change from country to country. Choose the market where you sell.
Run the check. The tool pulls both sites' rankings and compares them. A progress bar shows while it works.
Read the table. You get the top 20 gap keywords, sorted by search volume, and the total number of gap keywords above the table.
Sort and filter. Click a column header to sort by volume or difficulty. You can also sort by keyword or by the rival's position. Use the intent filter to show only the keywords that match your goal, like commercial keywords for a product page.
Copy or download. Copy the table to paste into a doc or sheet, or download it as a CSV file.

You get 5 checks a day for free. Results are saved for 7 days, so you can come back to the same pair and see the same list. Swapping the 2 domains counts as a new check, because the question is different.

How it works

The tool runs on DataForSEO Labs, a keyword and ranking database used by many SEO tools. DataForSEO tracks which pages rank in Google for a very large set of keywords. It also estimates how often each keyword is searched each month and how hard it is to rank for.

Here is what happens when you click run:

The tool cleans both domains, so https://www.yoursite.com/ and yoursite.com count as the same site.
It asks DataForSEO for the keywords where the rival ranks in Google's top 20 in your chosen country.
It checks your domain against those same keywords and drops every keyword where you rank anywhere in the top 100.
What's left is the gap. The tool counts it, sorts it by monthly search volume and shows the top 20.

The top 20 cut for the rival is on purpose. A rival at position 85 isn't getting real traffic from a keyword, so that keyword doesn't prove much. A rival in the top 20 is on page 1 or page 2, close enough to earn clicks.

The top 100 cut for you is also on purpose. If you rank at position 60, you have a page that Google connects to the topic. That's a weak spot to improve, which is a different job from a missing topic. The gap list only shows keywords where you have nothing in the top 100.

How close are the numbers?

Every number in the table is an estimate. Treat them as a guide to size and order.

Search volume is a monthly average from DataForSEO's data. Real searches go up and down with the season.
Keyword difficulty is a 0 to 100 score from DataForSEO. It mostly reflects how strong the pages are that rank today.
Rankings come from DataForSEO's latest crawl of the results page for that keyword. Google results change every day, so a position can be a few days old.
Search intent is a label DataForSEO gives each keyword based on what people seem to want.

Small keywords can be missing from the database, and very new pages can be missing from the rankings. If you launched a page last week, the tool may not see it yet. Your own Google Search Console data is the final word for your own site.

How to read your results

The result has 2 parts: the total gap count and the top 20 table.

The total gap count

The count tells you the size of the job. It counts every keyword that passes both rules, before the tool trims to 20.

Total gap keywords	What it usually means
Under 50	You cover this rival's topics well. Look for a handful of high-value pages to add.
50 to 500	A real gap. Your rival covers topics you skipped, often a whole content type like guides or comparison pages.
Over 500	The rival is far bigger in search, or works in a wider market than you. Filter hard by intent and fit.

These ranges are rough. A gap of 400 against a giant publisher means something different from a gap of 400 against a site your size.

The columns

Column	What it shows	How to use it
Keyword	The search people type into Google	Ask yourself whether your buyer would type it
Volume	Estimated searches a month in your country	Bigger is more traffic, if you can rank
KD	Keyword difficulty, 0 to 100	Lower is easier to break into
Intent	What the searcher wants to do	Match it to the page type you would build
Rival position	Where the rival ranks, 1 to 20	A rival at #15 is easier to pass than one at #2
Ranking page	The rival's URL that ranks	Open it to see what Google rewards

Reading keyword difficulty

KD	Rough meaning
0 to 29	Easier. A focused, useful page can often rank.
30 to 49	Medium. You need a strong page and some links or internal links.
50 to 69	Hard. Expect to need links from other sites and some time.
70 to 100	Very hard. Big brands hold these spots.

Keyword difficulty is a starting point. Your own site's strength changes the picture. A site with lots of links can win a KD 50 keyword faster than a new site can win a KD 25 one. You can check where you stand with the Domain Authority Checker.

Reading search intent

Intent	The searcher wants to	Page that usually fits
Informational	Learn something	A guide, how-to or explainer
Navigational	Reach a certain site or brand	Usually not worth chasing for another brand's name
Commercial	Compare options before buying	A comparison, "best of" or alternatives page
Transactional	Buy or sign up now	A product, pricing or sign-up page

What to do with your results

A gap list is only useful if it turns into pages. Here are 6 moves that work.

Cut the list to keywords that fit

Go down the 20 keywords and ask one question about each. Would a person who searches this want what you sell? Cross out the ones where the answer is no.

Your rival may rank for keywords that have little to do with your offer. They may run a free tool, a job board or a news section. Those pages bring traffic, but the traffic may not buy. You can skip them with a clear conscience.

Also cross out keywords with another brand's name in them, unless you're building an honest comparison page. Navigational searches for a rival's brand rarely convert for you.

Group keywords into pages

Many gap keywords belong on the same page. "Invoice template", "free invoice template" and "invoice template for freelancers" can share one page. Writing a page for each one splits your effort and makes the pages compete with each other.

Sort the list by theme. Give each group one target page. Pick the keyword with the biggest volume as the main one, and use the others in headings and the body where they read naturally.

To find more keywords for each group, run the main keyword through the Keyword Tool. It shows related searches and their volume.

Start with the best ratio of value to effort

Score each group on 2 things: how much you want the traffic, and how hard it is to rank. Volume and intent tell you the first. KD and the rival's position tell you the second.

A good first target often has medium volume, KD under 40, commercial or transactional intent and a rival sitting at #8 to #20. You can pass a rival who's on the edge of page 1 much sooner than one at #1.

Build 2 or 3 of these first. Early wins help you learn what Google rewards in your market.

Study the rival's ranking page

Open the rival's page for each keyword you plan to target. Read it like a buyer would. Note what it covers and how it's laid out. Then note what it offers that a plain article wouldn't.

Then search the keyword in Google yourself. Look at the other pages on page 1. If every result is a list of tools, Google wants a list. If every result is a template, Google wants a template. Match the format and then beat it on depth and clarity.

Don't copy the rival's page. Google has no reason to rank a copy. Add something they don't have: your own data, real screenshots, a worked example or a clearer answer.

Check the pages you already have

Sometimes a gap keyword belongs on a page you already have. Your pricing page may be the right place for a "cost" keyword. Your features page may be the right place for a "with time tracking" keyword.

In that case, update the page. Add a section that answers the search. Use the keyword in a heading. Then link to the page from other related pages on your site.

Before you edit, check the page loads fast and has no broken links. The Page Speed Checker and the Broken Link Checker take a minute each.

Track the new pages

Once a page is live, watch whether it ranks. You can spot-check a keyword any time with the Keyword Rank Checker. Expect most new pages to take weeks or months to settle.

Run the gap check again after a few months. If your pages now rank in the top 100, those keywords drop off the list. A shrinking count is a simple sign your work is landing.

Check more than one rival

One rival shows one slice of your market. Run the tool against 3 or 4 sites that compete with you in search. Keywords that show up in more than one gap are the strongest signals. Several sites rank for them, and you're missing from all of those results.

Want the whole picture in one place? Competitors in the Arrowsterr app shows the full gap for each rival, with every keyword beyond the top 20. It also shows the keywords you share, so you can see where you already compete.

Common mistakes

Picking the wrong rival

Many people enter the company they lose deals to. That company might be weak in search. The rival that matters here is the site that takes your Google traffic.

Fix: search 5 of your main keywords in Google and note which domains keep showing up. Use those as rivals. You can also check a site's size first with Domain Overview.

Chasing the biggest volume first

The top of the list is tempting. Those keywords also tend to have the highest difficulty. A new page rarely breaks into a KD 75 result.

Fix: sort by KD and look at the easier half first. Pick keywords you can win in the next few months, then work up.

Ignoring intent

A how-to keyword won't sell a product directly. A buying keyword won't rank with a long guide. Building the wrong page type is the most common reason a gap page never ranks.

Fix: use the intent filter, and look at the live Google results before you write. Build the page type Google already shows.

Writing one page per keyword

Close variants of the same search don't need their own pages. Separate pages for "crm for startups" and "startup crm" compete with each other.

Fix: group variants, give each group one page and use the variants inside that page.

Treating estimates as exact

Volume and KD are estimates. A keyword listed at 1,000 searches might get 600 or 1,500 in a given month.

Fix: use the numbers to rank keywords against each other. Check your real traffic in Google Search Console after the page goes live.

Comparing a subdomain by mistake

If you enter blog.yoursite.com, you compare only the blog. If your main pages live on yoursite.com, the result won't match your real coverage.

Fix: enter the domain your main pages live on. Run separate checks if your site is split across subdomains.

Running it once and stopping

Rankings change all the time. Rivals publish new pages. A gap list from last spring can miss the topics that matter now.

Fix: run the check every few months, or track rivals in the app so new gaps show up as they appear.

Glossary

Keyword gap. The set of keywords where a rival ranks and you don't. Here, that means the rival ranks in Google's top 20 and you're not in the top 100.

Search volume. The average number of times a keyword is searched in a month, in one country. It's an estimate.

Keyword difficulty (KD). A score from 0 to 100 for how hard it is to reach Google's first page for a keyword. Higher means harder.

Search intent. What a person wants when they search. The 4 common labels are informational, navigational, commercial and transactional.

Ranking position. Where a page appears in Google's results for a keyword. Position 1 is the top organic result.

Ranking page. The exact URL on a site that ranks for a keyword. One domain can rank with different pages for different keywords.

Top 20 and top 100. The first 20 and the first 100 organic results in Google. The top 20 covers about 2 pages of results.

Keyword cluster. A group of keywords that share one meaning and can be covered by one page.

Organic results. The regular Google results, without ads. Rankings in this tool are organic only.

Content gap. A topic your rival covers and you don't. A keyword gap is one way to find content gaps.

SERP. Search engine results page. The page Google shows after a search.

The AI search angle

Google isn't the only place your buyers ask questions now. They also ask ChatGPT. In Google, they read AI Overviews and switch to AI Mode. A keyword gap still matters in these places, but it works a little differently.

AI answers are built from web pages. Google AI Overviews and AI Mode lean on pages Google already ranks. ChatGPT search pulls from web results too. A topic you don't cover in Google is often a topic AI answers can't cite you for, because you have no page to cite.

So each gap keyword is also a prompt gap. "Best invoice app for freelancers" is a Google search. It's also a question people type into ChatGPT. If your rival has a strong page on it and you don't, the AI answer is more likely to name them.

Here's how to use your gap list for AI search:

Turn keywords into questions. Rewrite each gap keyword as the full question a buyer would ask an AI assistant. Use those questions as headings on your new pages.
Answer first. Put a clear, short answer at the top of each section. AI answers tend to quote pages that state the answer plainly. Check a page with the AI Answer-Ready Checker.
Let AI crawlers in. A great page is no use if AI crawlers are blocked from it. Run the AI Crawler Checker on your domain.
Point AI tools to your best pages. An llms.txt file lists the pages you most want AI tools to read. Make one with the llms.txt Generator.

Ranking in Google and showing up in AI answers aren't the same thing. They do feed each other. Closing your Google gap is one of the most direct ways to give AI answers something of yours to cite.

FAQ

What is a keyword gap analysis?

A keyword gap analysis compares the keywords your site ranks for with the keywords a rival ranks for. It shows the searches where the rival gets traffic and you don't. You use it to find topics to add to your site.

How do I find my competitors' keywords for free?

Enter your domain and a rival's domain in this tool and pick a country. You get the top 20 keywords the rival ranks for in Google's top 20 where you're not in the top 100. You get 5 free checks a day.

What counts as a gap keyword in this tool?

A keyword counts when the rival ranks in Google's top 20 for it and your domain doesn't rank anywhere in the top 100. Keywords where you rank at #40 or #90 are left out, because you already have a page Google connects to them.

Why do I only see 20 keywords?

The free tool shows the top 20 by search volume and the total count of all gap keywords. The full list, with every keyword and the keywords you share with the rival, is in Competitors in the Arrowsterr app.

Where does the data come from?

The rankings, search volume, keyword difficulty and intent come from DataForSEO Labs. It's a large database of Google rankings and keyword data. All the numbers are estimates.

How accurate is the search volume?

Search volume is a monthly average estimate. Real searches change with the season and with the news. Use volume to compare keywords with each other, and check real numbers in Google Search Console once you rank.

What is a good keyword difficulty score?

For a newer or smaller site, keywords under about 30 are the easiest place to start. Stronger sites can aim higher. Your site's links and authority matter as much as the score.

Can I compare more than one competitor at once?

This free tool compares one rival at a time. Run it once per rival and look for keywords that show up in more than one result. Those are your strongest targets.

Why doesn't the tool show a page I know ranks?

The data may be a few days behind Google, or the page may be very new. Small keywords can also be missing from the database. Check your own pages in Google Search Console for exact data.

Does it work for any country?

Pick the country where you want to rank. Rankings and search volume change by country, so the gap in one market can look very different from the gap in another.

Can I download the results?

Yes. You can copy the table or download it as a CSV file. The file opens in Google Sheets or Excel.

How often should I run a keyword gap check?

Every few months is a good rhythm for most sites. Run it again after you publish new pages to see whether those keywords drop off the list. Results are saved for 7 days, so a repeat check that week shows the same data.

Should I target every keyword in the gap?

No. Keep only the keywords your buyers would search and that fit what you sell. Then group close variants so one page covers each group.

What is the difference between a keyword gap and a content gap?

A keyword gap is a list of searches. A content gap is the missing topic or page behind those searches. You use the keyword gap to find the content gap, then build the page that fills it.

Keyword Tool: find related searches and volume for each gap keyword.
Keyword Rank Checker: check where your new page ranks in Google and AI Mode.
Domain Overview: size up a rival before you run a gap check.

Free keyword gap tool: what your rival ranks for and you don't

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