At a glance
Detects sudden, sharp increases in CPC at the keyword level. More aggressive than gads_cpc_anomaly (which uses 2σ threshold). This card fires when any keyword’s CPC doubles vs the 30-day baseline. CPC doubling without conversion-rate change halves ROAS instantly. The card protects the budget against runaway bidding caused by Smart Bidding misfires, competitor entry, or Quality Score collapse on a specific keyword.
| What it counts | Detects when any keyword’s current 24h CPC exceeds 2x its 30-day baseline. Reports the affected keyword and the current vs baseline CPC values. |
| Sample basis | Per-keyword Google Ads spend and click data, real-time. |
| Sampling threshold | n/a (full data). |
| Bot traffic filter | Google Ads invalid-click filter. |
| Time zone | Account time zone. |
| Time window | RT (rolling 24h vs 30D baseline) |
| Alert trigger | keyword_cpc > 2 × keyword_baseline_cpc |
| Sentiment key | gads_cpc_spike (alert variant) |
| Roles | owner, marketing, finance |
Calculation
Worked example
A UK-based BC store, CPC spike detection reading on Wednesday 15 May 26.| Keyword | 30D baseline CPC | 24h CPC | Multiplier | Status |
|---|---|---|---|---|
garden hose 30m | £1.50 | £1.62 | 1.08x | Normal |
bbq charcoal | £0.85 | £1.95 | 2.29x | Spike alert |
outdoor cushions | £1.20 | £1.34 | 1.12x | Normal |
lawn fertiliser | £0.95 | £1.05 | 1.11x | Normal |
patio heater | £1.80 | £4.20 | 2.33x | Spike alert |
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bbq charcoaljumped from £0.85 to £1.95. Likely cause: BBQ-season demand surge plus competitor entry. Multiple advertisers competing for seasonal high-intent queries simultaneously. -
patio heaterjumped from £1.80 to £4.20. Likely cause: cold-weather forecast triggering competitor bid increases. Patio heaters are weather-sensitive; a forecast of cold spring evenings drives bid pressure across the category.
- Seasonal demand surges trigger CPC spikes that Smart Bidding may chase past the profitability point. At £4.20 CPC × 100 clicks = £420/day on patio heater alone. If conversion rate is unchanged, the cost-per-acquisition jumps proportionally.
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Recommended response per spike:
bbq charcoal: confirm BBQ Charcoal Pro inventory is healthy (cross-referencebc_low_stock); if so, accept the higher CPC because seasonal demand justifies it. Conversion volume should rise alongside CPC.patio heater: cross-check; if patio heater is going OOS or seasonally winding down, pause this keyword temporarily rather than chase the spike.
- The Smart Bidding angle. Smart Bidding will chase rising auctions when it sees rising conversion likelihood. If conversion rate doesn’t keep up, Smart Bidding can dig a CPA hole quickly. Cap target-CPA settings so Smart Bidding can’t bid above breakeven.
- Brand vs non-brand consideration. Brand keyword spikes are rare (low competition, high QS); non-brand keyword spikes are common during seasonal events. The default config excludes brand keywords from spike detection to reduce noise.
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Recommended action workflow:
- Hour 1: Identify the affected keyword(s).
- Hour 2: Check inventory and conversion rate for the affected products.
- Day 1: Decide per keyword: accept the higher bid (if conversion volume justifies), pause keyword (if conversion can’t keep up), or set bid cap (if you want sustained presence at controlled cost).
- Day 2-3: If multiple keywords spike simultaneously, audit Smart Bidding strategy and target settings.
Sibling cards merchants should reference together
| Card | Why merchants reach for it |
|---|---|
gads_cpc_anomaly | Less aggressive 2σ variant. |
gads_alert_cpc_spike | Alert routing. |
gads_quality_score | Quality Score; major CPC driver. |
gads_cpa | Cost per acquisition; downstream effect. |
gads_roas | ROAS; collapses if CPC outpaces conversion. |
gads_total_spend | Total spend impact. |
Reconciling against the vendor’s own dashboard
Where to look in Google Ads: Reports → Keywords with sort by CPC; Auction Insights for competitive context. Why our number may differ:| Reason | Direction | What to do |
|---|---|---|
| Real-time vs reported. Google Ads reports lag 1-3 hours; this card uses real-time stream. | Vortex IQ may show signal earlier | n/a; earlier is better. |
| Brand keyword classification. Manual; not natively flagged. | Variable | Configure per-keyword in Vortex IQ. |
gads_quality_score for Quality Score detail.
Known limitations / merchant FAQs
Q: Why is the threshold 2x rather than 1.5x? 2x is the threshold for “structurally meaningful” spike that warrants action. 1.5x produces alert fatigue from normal variance. The 2σ statistical threshold (gads_cpc_anomaly) catches more subtle anomalies; this card catches the runaway cases.
Q: A keyword spiked but conversions are also up. Should I pause?
No, accept the higher CPC if conversion rate × AOV × margin still produces positive contribution. Smart Bidding chases rising auctions correctly when conversion likelihood is rising. The spike is a signal of demand, not a problem.
Q: A keyword spiked and conversions are flat. Should I pause?
Yes, or at least cap the bid. Rising CPC without rising conversion means Smart Bidding is misfiring, likely it’s seeing a high-intent signal that doesn’t translate to your store. Cap the keyword at the prior bid and observe.
Q: How does this differ from gads_cpc_anomaly?
That card uses 2σ statistical threshold (catches gradual creep); this card uses 2x absolute threshold (catches sudden doubling). The two complement each other: anomaly catches subtle changes, spike catches abrupt ones.
Q: Brand vs non-brand handling, why exclude brand?
Brand CPC is structurally £0.10-£0.50 with very tight variance. Even a 50% spike is a small absolute number (£0.20 to £0.30) and rarely indicates a real problem. Non-brand spikes are operationally meaningful.
Q: We use Performance Max, does this card work?
Partially. Performance Max doesn’t expose per-keyword CPC at the same granularity. The card can detect campaign-level CPC spikes but not the per-keyword detail available in standard Search campaigns.
Q: How do we set keyword-level bid caps?
In Google Ads: Campaign → Settings → Bidding → Bid limits. Set max-CPC at the level above which the keyword becomes unprofitable. Vortex Mind can recommend bid-cap values based on contribution-per-conversion math.
Q: Spike alerts firing 5x/week, too noisy?
Likely the threshold is too aggressive for your account size. Adjust to 2.5x or 3x in profile settings. Alternatively, exclude long-tail keywords from spike detection (they have natural variance from low click volumes).