A negative keyword stops your ad from showing on a search that is not for you (Google's definition of negative keywords). There are two ways to find them: plan them before launch, or pull them from the search terms of a live account. Optmyzr is the most complete on a live account; Should I Bid prepares negatives before you spend.
| Tool | Negatives from search terms | Negatives planned before launch | Keyword variants to screen | Free access and cost of entry | Total /5 |
|---|---|---|---|---|---|
| Optmyzr | 5 | 1 | 1 | 2 | 3.0 |
| Should I Bid (our tool) | 1 | 5 | 3 | 4 | 2.8 |
| Google Keyword Planner | 1 | 2 | 4 | 5 | 2.3 |
| Semrush | 1 | 3 | 4 | 3 | 2.3 |
| WordStream Free Keyword Tool | 1 | 2 | 3 | 5 | 2.2 |
| SpyFu | 1 | 3 | 3 | 3 | 2.1 |
| Keywords Everywhere | 1 | 3 | 3 | 3 | 2.1 |
| Adalysis | 1 | 1 | 1 | 2 | 1.2 |
Each tool gets a whole score from 1 to 5 on four weighted criteria, based on its official pages. A feature we could not verify is not counted. The heaviest criterion is the one Google itself points to for finding negatives: the search terms report.
Google advises looking for terms that are close to your keywords but serve people who want a different product. A solar installer in Phoenix does not sell RV solar kits, installer training, or jobs. Those searches still look a lot like theirs, and that is where the first wasted clicks come from.
The first way to block them is to plan ahead. Before launch you have no account data, but Google's results pages already show what people expect behind each query. The second way is to read what happened: the search terms report lists the real searches that triggered your ads. It is more precise, but some of those rows have already cost you clicks.
The two methods work together. They are part of a wider effort, covered in our guide to reducing wasted Google Ads spend, which also covers the ad quality summarized by Google Ads Quality Score.
On the Search Network, Google offers three match types for negatives: broad, phrase and exact. They do not behave like their positive counterparts: a negative does not apply to close variants, so you add synonyms and singular and plural forms yourself. Casing and misspellings are handled automatically.
Google adds two warnings. Too many negatives reduce the number of customers your ads can reach. And a negative that overlaps one of your own keywords stops the ad from showing: for the Phoenix installer, a broad match negative on 'solar' would shut down the whole campaign.
The grid scores eight tools on four criteria. The heaviest, at 45, covers negatives drawn from search terms: it is the method Google promotes, and the only one based on searches that actually triggered your ads. Negatives planned before launch weigh 25. The number of variants you can screen weighs 15, as does free access, which many people look for first.
Optmyzr comes first. Should I Bid follows thanks to pre-launch preparation, but it gets the lowest score on the main criterion, since it does not read an account's search terms. Keyword Planner and WordStream win on free access; Keyword Planner and Semrush on variant coverage.
Should I Bid starts from Google's results page, not from account history. For each keyword, it reads that day's ads and organic results, checks them against what your company sells, and returns a Bid, Test or Skip verdict with a score out of 100: Bid at 70 or above, Test from 50 to 69, Skip below 50.
Negatives come once per analysis. Keywords with a Skip verdict are suggested as exact match negatives. Around the keywords you keep, the tool suggests phrase match guardrails, each one checked against your company's keywords so you do not exclude something you are buying. Everything goes into a CSV export ready for Google Ads.
Take the Phoenix installer. If the results page for 'solar installer certification' mostly shows training programs, the query does not target a customer: it is a likely Skip, and therefore an exact match negative. This example shows the logic; the actual verdict depends on that day's results page. With no starting list, Vision generates ideas from a product or a URL. To decide keyword by keyword, see our guide on whether to bid on a keyword.
The first negative keyword tool is free and already in your account: the search terms report. Sort it by cost, spot the off-topic searches, and add them as negatives, at the account level, in a list shared across several campaigns, or in a single campaign. An account-level list applies to all eligible Search and Shopping inventory.
Optmyzr automates that work on existing accounts: negatives managed from search terms, scripts, automations and reporting. It pays off once there are too many terms to read by hand. Adalysis looks wider, at overall account health: over one hundred audit checks, budget monitoring, bids and ad testing, for Google Ads and Microsoft Ads alike. Its negative keyword features are not documented on its pages, hence the lowest score on that criterion.
Before launch, keyword research tools show you the universe around your terms. That is where the intents you do not want to pay for appear: free stuff, DIY, jobs, training, another product. Google Keyword Planner and WordStream Free Keyword Tool are free. Keywords Everywhere shows that data right inside Google. Semrush and SpyFu go further on competition and ad history. SpyFu also offers PPC negative match recommendations, and Keywords Everywhere a purchase-intent filter on its higher plans.
None of these tools gives a verdict against your offer: even an intent filter or label does not tell you whether a variant fits what you sell. They supply the raw material; the decision to exclude is still yours, by hand or with an intent tool.
We read each vendor's official pages, features and pricing, on the date shown in the verified prices table, along with Google Ads' help pages on negative keywords. The scores describe what each tool does according to those pages; none was tested on a real account for this comparison. The heaviest weight goes to the search terms report, because it is Google's own method, even though Should I Bid plays no part in it.
Should I Bid does not read your account's search terms and does not update your negatives week after week: Google's report and Optmyzr are built for that follow-up. It also does not do backlinks, organic rank tracking or technical SEO audits.
It works with credits, one credit per keyword analyzed, with free analyses to try it and no credit card (see the pricing page). The goal is the same as your negatives: stop paying for clicks that cannot convert.
| Tool | Starting price | Details | Source |
|---|---|---|---|
| Should I Bid | Per credit (see Pricing page) | Per credit (1 credit = 1 keyword analyzed), free analyses to try, no credit card. Plans described on the Pricing page. | Source |
| Optmyzr | Not verified (dynamic pricing) | Priced by monthly ad spend tier ($25k to $500k+), Essentials / Premium / Enterprise plans, 30% off annually, 14-day trial. Amounts rendered dynamically: not captured. | Source |
| Adalysis | Not verified (dynamic pricing) | Priced by monthly ad spend (slider), Starter / Professional / Enterprise plans, 10% (6 months) and 15% (annual) discounts, 30-day trial. Dynamic amounts: not captured. | Source |
| Google Keyword Planner | Free | Free with a Google Ads account. Exact volumes require an account with active spend, otherwise ranges. | Source |
| Semrush | from $139/mo ($117.33/mo billed annually) | Entry “SEO” plan: $139 per month billed monthly, $117.33 per month billed annually. 7-day trial, limited free plan. Separate “Advertising” toolkit: Base plan at $99 per month. | Source |
| SpyFu | from $39/mo ($29/mo billed annually) | “Basic” plan: $39 per month billed monthly, $29 per month billed annually. “Pro + AI”: $59 the first month, then $119 per month ($89 annually). 30-day guarantee. | Source |
| Keywords Everywhere | from $84/yr | Annual subscriptions: Bronze $84 per year (100,000 credits), Silver $168, Gold $480, Platinum $1,440. 1 credit = 1 keyword, credits valid one year. | Source |
| WordStream Free Keyword Tool | Free | Free: first 25 keywords on screen, full list as a CSV in exchange for an email address, unlimited searches. | Source |
Prices verified on . Public prices observed on the vendors’ websites on the date shown. They may have changed since: the source prevails.
It is a term you add to a campaign, an ad group or the whole account so your ads do not show on searches that contain it. It filters out searches that look like yours but are about a different product, so your budget goes to people who might actually buy. Google treats it as a way to target only what matters to your customers.
With negative broad match, the ad is blocked when the search contains all the excluded terms, in any order. With negative phrase match, the terms must appear in the same order, and other words may be added. With negative exact match, only the identical search, with no extra words, is blocked. Broad match is the default negative type.
Start from your keywords and look at what surrounds them: Keyword Planner ideas, the questions people ask, Google's results pages. Note the intents you do not serve, such as jobs, training, free versions or another product. Should I Bid automates that screening by reading each keyword's results page and suggesting negatives with every analysis.
Plurals, yes. Google states that negatives do not cover close variants, so you need to add synonyms and singular and plural forms yourself. Misspellings and casing, however, are handled automatically. Accents matter too: a negative with and without an accent counts as two separate negative keywords.
Yes. Google warns that too many negatives reduce the number of customers your ads can reach. A negative that overlaps one of your keywords even stops the ad from showing. That is why every negative should be checked against your keyword list before you add it, especially a one-word broad match negative.
The most useful one is already free: the Google Ads search terms report, which shows the real searches that triggered your ads. To prepare a list before launch, Google Keyword Planner and WordStream Free Keyword Tool cost nothing. Should I Bid offers free analyses to try it, with no credit card, and then works with credits.