How to Do Keyword Research for Google Ads (2026)

By Nick Quirk September 8, 2026 9 min read

Learning how to do keyword research specifically for Google Ads means judging every phrase by what it costs and what it converts, not by how much traffic it could send. A term with 40 searches a month can outperform one with 20,000 if the people typing it are ready to buy. This guide walks through the full process: sourcing ideas, validating them in Google Keyword Planner, scoring intent, budgeting by cost per click, and using the search terms report to finish the job after launch.

Paid Keyword Research Is a Different Job From SEO

SEO keyword research rewards volume and topical breadth, because a single article can rank for hundreds of related phrases at no extra cost. In Google Ads, every click is billed, so breadth is a liability rather than an asset. The goal shifts from “what could I rank for” to “which searches am I willing to pay $3, $12 or $60 to answer”.

That difference changes three things in practice:

Volume matters less than intent. Ten searches for “emergency plumber near me open now” beat a thousand for “how does a P-trap work”.
Cost per click becomes a filter. If your average order value is $80 and a keyword’s top-of-page bid is $22, the maths rarely works.
Negative keywords are part of the research, not an afterthought. Deciding what you refuse to pay for is half the work.

If you have not run a campaign before, it helps to read our walkthrough on launching your first Google Ads campaign alongside this, since account structure and keyword selection are decided together.

Step 1: Do the Budget Maths Before You Open Any Tool

Work backwards from what a customer is worth to you. If your average sale is $400 with a 30% margin, you have roughly $120 of gross profit to spend on acquiring that customer, and a sensible target is spending a third to half of that per sale.

Then apply a rough funnel: most search campaigns convert visitors to leads at somewhere between 3% and 8%, and lead-to-sale rates in service businesses commonly land between 20% and 40%. At a $5 cost per click, a 5% conversion rate means a lead costs about $100 before you close anyone. That single calculation tells you which keywords are affordable and which are vanity targets.

Step 2: Harvest Keywords You Already Own

The best starting list is not invented, it is collected. Before touching a research tool, pull ideas from sources that already reflect how your customers speak.

Your own site copy. Service pages, product titles and category names are the phrases you already claim to sell.
Google Search Console. Filter queries by impressions and look for commercial phrases where you rank on page two or three. Those are proven demand you are currently losing.
Sales calls, live chat and email. Write down the exact wording people use when they describe the problem, including the wrong words.
Competitor ads. Search your core terms in an incognito window and read the ad copy, then check the Google Ads Transparency Center to see what rivals are actively running.
Internal site search. If your site has a search box, the query log is a short list of high-intent language.

Aim for 60 to 150 raw phrases at this stage. Messy is fine, you will cut most of it.

Step 3: Validate and Expand With Google Keyword Planner

Google Keyword Planner is free with any Google Ads account, though you need to create the account (a campaign does not have to be live). Use the “Discover new keywords” tool with five to ten seed terms plus your domain, then switch to “Get search volume and forecasts” to check the list you built in step two.

Two details trip people up. First, accounts with little or no spend see bucketed volume ranges such as 100 to 1K instead of exact figures, which is enough for prioritising but not for forecasting. Second, the numbers you want are not the search volume columns at all, they are top of page bid (low range) and top of page bid (high range), because those tell you what the auction actually costs. Google’s own Keyword Planner documentation explains how the forecast columns are calculated.

For a closer look at this topic, see our guide: The Anatomy of a High-Converting Google Search Ad.

We cover this topic in more depth in Search Network vs. Display Network: When to Use Which.

Set your location and language before you export, otherwise national averages will distort local pricing. A term that costs $6 nationally might cost $2.40 in one metro and $14 in another.

Third-Party Tools Worth Adding

Keyword Planner hides long-tail variants it considers close duplicates, so a second source helps. Semrush, Ahrefs and Ubersuggest all surface competitor paid keywords and historic ad copy, which is faster than manual searching. Free options such as AnswerThePublic and the Google autocomplete dropdown are still useful for question phrasing.

Step 4: Score Every Keyword by Commercial Intent

This is the step most guides skip, and it is where budgets are saved. Sort your list into four intent tiers and fund them in order.

Tier 1, transactional: includes “buy”, “hire”, “near me”, “quote”, “price”, “cost”, “same day”. Highest cost per click, best conversion rate, fund these first.
Tier 2, brand and competitor: your own name (cheap, defensive) and competitor names (legally allowed as keywords in most markets, but you cannot use their trademark in ad text).
Tier 3, category and comparison: “best CRM for small business”, “X vs Y”. Longer sales cycle, worth testing with a capped budget.
Tier 4, informational: “how to”, “what is”, “DIY”. Excellent for blog content, usually a poor use of ad spend unless you are running remarketing off the traffic.

A practical rule for small accounts: put 70% of budget in tier 1, 20% in tiers 2 and 3, and leave tier 4 to organic search.

Step 5: Build the Negative Keyword List Before You Launch

Every keyword idea you rejected belongs in a negative list. The standard blockers for most businesses are free, cheap, DIY, jobs, salary, course, template, pdf, reddit and how to become. Add industry-specific ones: a commercial roofer blocks “residential”, a B2B software firm blocks “student” and “crack”.

Build these as a shared negative list at account level so it applies everywhere. Thirty to fifty negatives on day one commonly cuts wasted spend by a fifth in the first month, and the list should keep growing weekly.

Step 6: Group Keywords Into Tight Ad Groups and Choose Match Types

Once the list is clean, cluster it by the page you would send the click to. If two keywords need different landing pages or different headlines, they belong in different ad groups. Five to fifteen closely related keywords per ad group is a workable range for most accounts.

Match type decides how far Google can stray from your wording, and it interacts with your budget. Phrase and exact match give tighter control on small budgets, while broad match with a strong negative list and smart bidding can find volume once you have conversion data. Our breakdown of broad, phrase and exact match types covers when each one earns its place.

Step 7: Let the Search Terms Report Finish the Research

Pre-launch research is a hypothesis. The real data arrives once ads run, in the search terms report, which shows the actual queries that triggered your ads rather than the keywords you bid on. Review it twice a week for the first month, then weekly.

Do three things with every review: add converting queries as their own exact match keywords, add irrelevant queries as negatives, and note phrasing patterns you had not considered. Most accounts discover 15% to 30% of their eventual best performers this way, not in the planner.

Mistakes That Quietly Drain Budget

Bidding on single generic words like “insurance” or “software” on a small budget.
Sending every keyword to the homepage instead of a matching page.
Judging keywords on click-through rate rather than cost per conversion.
Never revisiting the list, so seasonal and outdated terms keep spending.
Running ads without conversion tracking, which makes the whole exercise guesswork.

Frequently Asked Questions

Is $20 a day good for Google Ads?

$20 a day (about $600 a month) is workable for a local service business with cost per click under $5, giving you roughly 120 to 200 clicks monthly. It is too thin for competitive national terms where clicks run $15 or more, since you would buy only one or two clicks a day and never gather enough data to optimise.

Can I use ChatGPT for keyword research?

Yes, for idea generation and clustering, but not for search volume or cost data, which it cannot access accurately. Use it to brainstorm variants, group terms by intent and draft negative keyword lists, then validate every phrase in Keyword Planner before you bid.

How do I add keywords in Google Ads?

Open your campaign, select the ad group, click the Keywords tab, then the plus button, and paste one keyword per line with your chosen match type. Wrap phrase match in “quotation marks” and exact match in [square brackets]; plain text defaults to broad match.

How do I search for specific keywords in Google?

Put the phrase in quotation marks for an exact-phrase search, and add operators such as site: to limit results to one domain or -word to exclude a term. This is a quick way to check who else is advertising and how competitors word their offers.

Want a Second Pair of Eyes on Your Keyword List?

If you would rather have someone audit your account structure, negatives and bids before you spend another month guessing, get in touch with SEO Quirk and we will look at your actual search terms data. There are also solid reasons to keep this work close to home, which we cover in the benefits of a local agency.

How to Do Keyword Research specifically for Google Ads