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Wasted Ad Spend Calculator
Answer six questions about how your account is set up. You get back a range, not a fake precise number, the three most likely places the money is leaking, and one thing to go check first.
Fill in the form and press Calculate. Your estimate appears here.
How this is calculated
This is a rule-of-thumb model, not a benchmark pulled from a study, and we are not going to pretend otherwise. Every band below is an assumption we chose and are showing you plainly, not an industry statistic. If you disagree with an assumption, the math is simple enough to redo in your head with your own number instead.
Broad match band: 8%–20% of the spend allocated to broad match
Broad match lets Google's matching system decide which searches count as a match instead of you choosing the exact phrasing. That mechanically raises the odds of matching searches with no real commercial intent, especially without a current negative-keyword list. We assume a fifth to a twelfth of that broad-match spend misses, scaled to the percentage you told us.
Performance Max / Advantage+ band: 5%–15% of total spend when on
Both are black-box campaign types by design: Performance Max does not break spend out by individual placement or search-partner site the way a standard Search campaign does, and Advantage+ auto-expands placements across Feed, Reels, Stories, and the Audience Network without a default per-placement view. You cannot audit what you cannot see, so we assume a meaningful minority of that spend goes somewhere you would not have chosen if you could see it. When you told us "not sure," we count this band at half weight.
Auto-apply recommendations band: 3%–10% of total spend when on
This setting lets the platform add keywords, raise budgets, loosen bid strategies, or remove restrictive settings automatically. Our reading of how Google documents this feature is that most of the recommendations it applies expand reach and spend rather than tighten it. Half weight when you told us "not sure."
Baseline band: a flat 2%–5% of total spend
Applied regardless of your other answers. Almost every account that has not had a search-terms report and placement review in the last month accumulates some drift. This is the smallest band on purpose.
The ceiling
We cap the high end of the range at 40% of your stated monthly spend. We do not think any account, however neglected, is reasonably modeled as wasting more than that on average, and a higher number would stop being useful and start being a scare tactic.