"We need to find out which keywords our competitor is advertising on in Google. People say you check it on SEMrush — does anyone have an account, should we pay for one?" Plenty of teams have this exact conversation. The good news: there are genuinely useful, largely free methods for competitor ad research. The bad news (and the most important part of this article): there is no free method that gives you a competitor's exact keyword list and budget with 100% accuracy. Confusing those two is exactly why many teams end up paying for the wrong tool.

In this article we first set the expectation straight, then walk through the genuinely free methods one by one, and finish with a practical workflow that chains them together.

First, fix the expectation: these are two different things

"Competitor ad research" actually hides two different questions that people constantly mix up:

  • 1. Which ads is the competitor running? (ad copy, images, video, landing page, which country and when) → This is available free and officially.
  • 2. Exactly which keywords are they bidding on and how much do they spend? → Google never shares this. Tools like SEMrush, Ahrefs and SpyFu estimate it; it's not hard data, and the good part is paid.

So Google Ads Transparency Center — the tool everyone mentions — is real and powerful, but it does not give you a keyword list. It shows you the ads themselves. Knowing this distinction stops you from buying a subscription you don't need.

1. Google Ads Transparency Center — free, official, unlimited

This is Google's own transparency tool and it's completely free: adstransparency.google.com. You type in a brand name or domain, and it lists the ads that advertiser is running on Google (Search, Display, YouTube).

What you see:

  • The exact ad copy, images and videos being run.
  • Which region/country the ad is shown in.
  • The ad's first and last shown dates (i.e. how long it's been running).
  • The advertiser's verified identity.

It does not give keywords — but it doesn't need to. Once you read 20-30 of a competitor's ad texts, you clearly see which products, campaigns and messaging themes they're leaning into. "Are they emphasizing a discount, free shipping, being enterprise-grade, or price?" — the answer is right here. It's not a keyword list, but it is a snapshot of their strategy.

Tip: The equivalent on the Meta (Facebook/Instagram) side is the Meta Ad Library — equally free and official for social ads.

2. Manual search in incognito — the crudest but most certain

You search for keywords you suspect in your browser's incognito (private) window and see whether the competitor's ad appears. Why incognito? Because in a normal tab your search history and cookies distort the results. Why does it matter? Because this method answers "is the competitor advertising on this keyword or not?" with 100% certainty — not an estimate, a live observation.

Even better: search from the target region. You can change region in Google's search settings or use a VPN for a different city/country, because ads vary by location. The downside is that it doesn't scale — perfect for 5 keywords, exhausting for 500.

3. Google Keyword Planner — free

Used free with a Google Ads account. It's not competitor-specific, but it's invaluable for two things:

  • Search volume: how many times a keyword is searched per month.
  • Competition and estimated bid (CPC): how expensive that keyword is for advertising.

The workflow: extract themes from the competitor's ad copy in Transparency Center → enter keywords for those themes into Keyword Planner → see which ones are high-volume and expensive, i.e. the keywords the competitor is most likely spending on. You don't get their exact list, but you've prioritized the most likely and most valuable keywords.

4. The free quotas of paid tools — use them smartly

Tools like SEMrush, SpyFu, Ahrefs and Ubersuggest produce an estimate of "this site pays for these ad keywords" when you enter a domain. Two important points:

  • This is an estimate. The tools don't get secret data from Google; they infer it from their own clickstream data and observations. Accuracy varies by brand, country and industry.
  • Most tools give a few free queries per day. For 2-3 competitors that free quota is usually enough — you get insight without subscribing. SpyFu in particular offers a limited but generous free view for competitor ad keywords.

So the answer to "does anyone have a SEMrush account, should we pay?" is usually: try the free quota before paying. If you're only checking a handful of competitors, a subscription is unnecessary.

So why isn't the "exact keyword list" free (and certain)?

Because the keywords an advertiser bids on are private data inside their Google Ads account. Google exposes this to neither competitors nor third parties. Third-party tools "estimate" the list like this:

  • They search millions of keywords themselves and observe which sites show ads (SERP scraping).
  • They model real clickstreams from browser-extension/panel data to estimate volume and cost.

That's why two different tools can give different lists for the same competitor. None is "wrong"; all are estimates. The only way to certainty is either accessing the competitor's account (impossible) or searching the keyword in incognito and seeing the ad live (method 2).

Practical workflow: combine the free tools

The best result comes not from one tool but from chaining these methods:

  • Step 1 — Discovery: Read all of the competitor's active ads in Transparency Center + Meta Ad Library. Note the messaging themes and highlighted products.
  • Step 2 — Keyword generation: Build a keyword list from those themes; expand it with the SpyFu/SEMrush free quota.
  • Step 3 — Prioritization: Enter the keywords into Keyword Planner and sort by volume and CPC. High volume + high CPC = where the competitor likely invests.
  • Step 4 — Verification: Search the 10-20 most critical keywords in incognito, from the target region, to confirm the competitor's ad actually shows.
  • Step 5 — Action: Decide whether to compete on the keywords they're strong on, or play the keywords they've left empty (no ad showing) — build your strategy accordingly.

All of the methods above are fully legitimate: viewing public ads, searching keywords, and using official tools. The only things to watch are respecting each tool's terms of use (no automated/aggressive scraping) and not using the information in a misleading or unfair-competition way. The goal of competitor analysis isn't to copy — it's to position yourself more intelligently.

Summary

The free answer to "which keywords is the competitor advertising on?" is: you can see the ads themselves (Transparency Center) officially and without limits, certainly confirm whether they advertise on a keyword via incognito, prioritize keywords with Keyword Planner, and expand the estimated list with paid tools' free quotas. For anyone wanting an exact keyword + budget table, there's no free and certain path — only paid tools' estimates. For most teams, though, this free combination is more than enough.

With Partnerfy

If you want to turn competitor analysis into a proper process, advertise on the right keywords with the right budget, and get ahead on the organic side too, this is what we do: end-to-end setup across SEO, marketing automation and AI-powered marketing. Let us analyze your competitors and build a tailored Google Ads and content strategy for you — get in touch.

Sources