Rankfill

Compare Keywords With Competitors to Spot Content Gaps

You check your analytics. Traffic is flat. You publish more content. Still flat. Then you look at a competitor's site — a company you know isn't smarter or better resourced than you — and they're ranking for dozens of terms you never even considered targeting. You're not losing because their content is better. You're losing because they've covered ground you haven't mapped yet.

That's what a keyword comparison actually reveals: not who writes better, but who has built more surface area.

What You're Actually Looking For

When you compare keywords with competitors, you're hunting for three things:

Gaps — keywords they rank for that you don't. These are the clearest opportunities because the traffic demand is already proven.

Overlaps — keywords you both rank for. Here you can compare positions. If they're ranking #3 and you're ranking #14, that's a winnable fight with better content.

Blind spots — keywords neither of you ranks for yet, but that real buyers are searching. These take more work to find but carry less competition.

Most people focus only on gaps. That's fine as a starting point, but the overlap analysis often surfaces faster wins.

How to Pull the Comparison Data

You need a tool that shows keyword rankings by domain. The main options:

Ahrefs — Site Explorer → enter a competitor's domain → "Organic keywords." Then use the Content Gap tool (under Competitive Analysis) to enter your domain against theirs. It shows keywords they rank for that you don't.

Semrush — Keyword Gap tool. Enter your domain and up to four competitors. It returns a matrix showing who ranks for what, with filters for "Missing" (they have it, you don't) and "Weak" (you both rank, but they outrank you).

Moz — True Competitor and Keyword Gap tools work similarly, though the keyword database is smaller than Ahrefs or Semrush.

Google Search Console — Free, but limited. It only shows keywords your site already ranks for. It can't show you competitor rankings directly. Use it to identify your existing positions, then compare against competitor data from one of the paid tools.

If you're just starting out and don't have a paid tool subscription, you can get partial data by using Ahrefs' free site checker or Semrush's free tier (limited to 10 results per report). It won't be complete, but it's enough to see the shape of the gap.

For a deeper walkthrough of the mechanics, Competitor Keyword Analysis: Uncover What You're Missing covers the full process step by step.

How to Run the Comparison Without Getting Lost in Data

Pull the gap report. You'll get hundreds, sometimes thousands, of keywords. Here's how to cut through it:

Step 1: Filter by relevance

Sort the list to remove keywords that are clearly off-topic. If your competitor sells accounting software and also published a recipe blog post that ranks, those keywords aren't your target.

Step 2: Filter by volume and difficulty

Set a minimum monthly search volume (at least 100 for most niches, lower if yours is very specialized). Set a maximum keyword difficulty — I'd suggest starting below 50 if your site is newer, below 70 if you have solid domain authority.

Step 3: Group by topic

You'll notice clusters — five keywords about the same concept, phrased differently. Don't create five pages. Create one page that addresses the full topic. The keyword research competitor analysis guide goes into grouping methodology in detail.

Step 4: Check the SERP before committing

For every keyword cluster that looks promising, actually Google it. Look at what's ranking: Is it blog posts? Product pages? Forum threads? If the top results are Reddit and Quora, the searcher wants opinions, not a guide. Build what matches the format of what's already winning.

Reading the Gap Report Correctly

A gap isn't automatically an opportunity. Before you add something to your content plan, ask:

Is this buyer-adjacent? A keyword might get 5,000 searches/month but attract an audience that will never buy from you. Traffic that doesn't convert is just a vanity metric.

Can you rank for it? A keyword with difficulty 85 and ten authoritative domains in the top 10 results isn't worth pursuing right now unless you're willing to invest significantly in link building alongside the content.

Does your site have the authority to compete here? If a keyword is dominated by sites with DR 80+ and your site is DR 35, you'll need to either build authority first or find lower-competition alternatives that cover the same buyer intent.

How to Find and Target Your Competitor Keywords has a practical framework for prioritizing which gaps to actually chase versus which to park for later.

The Overlap Analysis (Don't Skip This)

Once you've worked through the gaps, go back to the overlapping keywords — the ones you both rank for, but where they outrank you.

Filter the overlap list to show keywords where you rank between positions 5 and 20. These are your near-wins. You're indexed, Google considers you relevant, but your page isn't quite good enough to beat theirs.

For each of these, look at what they've built versus what you've built:

Often the answer is one of the first two, and you can fix that with a content update — no new link building needed. This is frequently the highest-ROI move in a competitive keyword analysis. See competitor keywords and rank for them too covers the reoptimization process if you want to dig into it.

Building a Content Plan From the Data

Once you have your filtered, grouped, prioritized keyword list, the next step is sequencing:

  1. Quick wins first — low difficulty, decent volume, clear buyer intent, your site is already competitive in the space
  2. Pillar content second — high-volume topics that will take real effort but will anchor your site's topical authority
  3. Supporting content third — lower-volume, long-tail pages that feed into your pillars and capture specific buyer questions

For most sites, the right cadence is one pillar per month and two to four supporting pieces per week — if you have the resources. If you don't, publish less but publish consistently. A gap analysis does nothing if you don't act on it.

If you want someone to map all of this for you — competitors identified and scored, every keyword gap surfaced, monthly traffic potential estimated, and a full content plan built — Rankfill does exactly that as a one-time engagement, no subscription required.

FAQ

What tools can I use to compare keywords with competitors for free? Semrush and Ahrefs both have limited free tiers. Google Search Console shows your own rankings but not competitors'. For a complete picture, you'll need a paid tool or a one-time report.

How many competitors should I compare against? Start with three to five. More than that and the data gets unwieldy. Focus on competitors who rank for the same buyer-intent keywords you want, not just anyone in your industry.

How often should I run a keyword gap analysis? Every quarter is a reasonable cadence for most sites. Competitors publish new content continuously, so gaps evolve. Running it once and never returning means you'll miss new opportunities they're capturing.

Should I target every keyword gap I find? No. Most of the gap list will be irrelevant, too competitive, or not buyer-adjacent. The filtering steps above exist precisely because raw gap data includes a lot of noise.

What if my site is new and has no authority? Focus on keywords with difficulty below 30 and volumes above 50. Build topical authority in a narrow niche first before expanding. A keyword competitive analysis run against smaller, newer competitors in your space will surface more realistic targets than benchmarking against established players.

Does a keyword gap mean I'm definitely losing traffic to that competitor? Not necessarily — it means they're capturing traffic from that term and you're not. Whether that audience overlaps with yours depends on the keyword's intent. Investigate before assuming every gap is a problem you need to solve.