The Cannibalization Report — Issue I
Catch the Google Ads waste Performance Max hides from you
Connect Google Ads in 60 seconds. We'll show you exactly how much PMax is silently spending on the branded queries your Search campaign already covers — and alert you every morning when it bleeds again.
§1 The leak Google won't name
Performance Max is the only Google Ads campaign type that does not surface a keyword report. The advertiser uploads creative, names a budget, sets a goal — then cedes auction logic to Google's AI. The AI, optimizing for conversions, bids on whatever query it can win — including branded queries already covered by your Search campaign at a fraction of the cost. The result: two of your own campaigns bidding against each other in the same auction. PMax wins, you overpay.
This is not a bug. Google built the product this way and advertisers have, until recently, lacked the tooling to detect it.¹
§2 How the audit runs
Connect Google Ads
OAuth in 60 seconds. Read-only access. We never edit your campaigns.
scope: adwords (read-only)
Detect cannibalization
We pull PMax search-terms + Search keywords. Compute waste per term.
GAQL · search_term_view + keyword_view
Telegram, every morning
Daily alert at 9 AM EST when cumulative waste crosses your threshold.
cron · 13:00 UTC · idempotent
§3 The receipt — a real audit, redacted
30-day · annualized
$4,988
= $415.69 detected, last 30 days
Five branded queries where PMax CPC ran 4.4× higher than what your Search campaign was already paying. Sorted by waste descending.
| Search term | PMax spend | PMax CPC | Search CPC | Waste |
|---|---|---|---|---|
| acme coffee | $246.56 | $1.84 | $0.42 | $190.27 |
| acme dark roast | $133.63 | $1.61 | $0.38 | $102.46 |
| buy acme coffee | $98.60 | $1.45 | $0.51 | $63.92 |
| acme single origin | $61.57 | $1.31 | $0.62 | $32.43 |
| acme cold brew | $44.84 | $1.18 | $0.47 | $26.61 |
| Total · 30 days | $585.20 | $415.69 |
Source: PMax Sentinel detection algorithm against Acme Coffee Co.'s Google Ads search-term-view, last 30 days. See live demo →
§4 Why not buy Optmyzr
You can pay $249/mo for sixty features you don't use, or pay $19 for the one that matters.
Optmyzr
$249–2,499 / moAnnual contract · 60+ features
- Bid optimization across 17 strategies
- Quality Score tracker
- Negative keyword finder
- A/B ad copy testing
- Budget pacing alerts
- Account audit (47 categories)
- Shopping feed optimizer
- PMax cannibalization detection
- Auction insights weekly digest
- Anomaly detection
- White-label client reports
- Slack · Looker Studio · API access
- + 47 more features
PMax Sentinel
$19 / moCancel any time · 1 feature
- PMax cannibalization detection
The argument is the layout. The single thing both products do — surfaced for the cost of two coffees, on a personal credit card, no procurement.
§5 Terms
$19 per Google Ads account, per month. No annual contract. Cancel any time.
Most customers monitor one to three accounts. Stripe-secured checkout. The first audit is free — connect your account, see the dollar number, then decide.
Start free auditCurrently watching 1 Google Ads account · accepting new accounts
p99 audit latency: 2.4s · cron uptime: 100.0%
Sources & footnotes
- ¹Optmyzr (Feb 2025). Performance Max Cannibalization in Google Ads: An Analysis of 1,800 Accounts. 91.45% of audited accounts showed PMax bidding on branded queries already covered by Search campaigns.
- ²Google Ads API Reference, search_term_view and keyword_view entities. PMax Sentinel queries both, last-30-days segment, via GAQL.
- ³Mike Rhodes, v28 of the Google Ads cannibalization script (open-source). Inspiration for the detection threshold; PMax Sentinel productizes the same waste-vs-Search-CPC ratio (≥1.5×) into a managed daily audit.