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Card class: Hero • Category: Ads

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At a glance

Alerts when Google Ads conversions drop significantly versus a recent baseline. A 25%+ overnight conversion drop is rarely a real demand drop, it is almost always a tracking failure: GTM tag broken, conversion goal misconfigured, conversion linker disabled, or the BC checkout-event GTM tag stopped firing. The card is the early-warning signal that catches conversion-tracking gaps before the merchant burns through 7-14 days of ad spend on data the platform can’t optimise.
What it countsDetects when current-period conversions fall below a rolling-baseline threshold. The threshold is dual: (a) absolute drop greater than 15% over the rolling 7-day window vs the prior 7-day window, OR (b) absolute drop greater than 25% in any 24-hour period. Either trigger fires the alert.
Sample typeGoogle Ads conversions (purchases) data, refreshed on the standard data refresh.
Why this alert matters(1) Catches tracking failures fast: most conversion drops are tracking issues; the 24-hour trigger catches them within a day rather than a week. (2) Protects ad spend: Google Ads bidding optimises against conversion data. Broken tracking sends Smart Bidding into the dark, leading to wasted spend. (3) Diagnoses release regressions: GTM tag changes, theme updates, BC integration changes can all break conversion firing without obvious symptoms.
Reading the value(1) No alert: conversions tracking normally. (2) Alert with 15-25% drop: investigate but may be real demand softening. (3) Alert with 25%+ drop in 24h: almost certainly a tracking issue; pause investigations and check GTM. (4) Cross-reference gads_total_revenue and BC’s total_orders for the ground-truth sales picture.
Currencypercent (drop magnitude).
Time window7D vsP rolling, with 24h sub-window for sudden drops.
Alert triggerconversions_change_pct < -15 (over 7D) OR conversions_change_pct < -25 (over 24h).
Sentiment keygads_conversion_drop_alert (alert state when triggered).
Rolesowner, marketing, operations

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Calculation

gads_conversion_drop_alert fires when:
  (current_7d_conversions - prior_7d_conversions) ÷ prior_7d_conversions × 100 < -15
  OR
  (last_24h_conversions - average_24h_baseline) ÷ average_24h_baseline × 100 < -25
The 24h trigger uses a rolling 7-day baseline average to avoid false positives on weekend/weekday mix.

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Worked example

A UK-based BC store, conversion drop alert reading on Wednesday 15 May 26.
PeriodConversionsChangeNotes
7 days ago - today213-22.4%Alert fired
Prior 7 days274baseline-
Last 24h22-42%Severe sub-window drop
24h baseline (rolling 7d avg)38/day-Expected
Cross-reference signals:
  • BC total_orders last 7 days: 462 (BC-side sales unchanged; Google Ads “lost” the conversions despite real sales)
  • gads_total_spend unchanged at £45K
  • gads_ctr unchanged at 3.2%
  • Recent release deploy: GTM container update on Monday 13 May (2 days before alert)
What the alert is telling us:
  1. Sales are actually fine; tracking is broken. BC reports 462 orders (real sales), Google Ads reports 213 conversions. Google Ads is missing roughly half the conversions. This is conversion-tracking failure, not demand drop.
  2. Smoking gun: GTM update on Monday. The release timing aligns with the conversion drop start. Likely cause: GTM container was updated, conversion linker tag disabled or broken, conversion event firing condition changed.
  3. The financial impact of letting this run:
    • Google Ads Smart Bidding optimises based on conversion data. With half the conversions invisible, bidding optimises for the wrong audiences and decisions.
    • 7-14 days of broken tracking can result in 20-40% wasted ad spend as Smart Bidding degrades.
    • In this case: 7 days × £6,500/day spend = £45,500 of ads optimised on broken data.
  4. Recommended response, in priority order:
    • Hour 1: Verify in Google Ads the conversion event is firing as expected. Use the Google Ads Tag Assistant.
    • Hour 1: Check the GTM container changelog for any changes to: conversion linker tag, purchase event tag, BC integration trigger.
    • Hour 2: Test the checkout flow; check that purchase event fires in browser console.
    • Day 1: Roll back the GTM container change if the broken tag is identified.
    • Day 1: Use Google Ads’ “Conversion adjustment” feature to retroactively credit the missed conversions if possible.
    • Day 2-7: Re-train Smart Bidding on the corrected data; expect 7-14 days for bid optimisation to recover.
  5. What to NOT do:
    • Don’t pause campaigns yet. Pausing during a tracking issue means the resumed campaigns lose all bid history.
    • Don’t accept the alert as a real demand drop without checking BC’s order data. Always cross-reference BC total_orders first.
    • Don’t manually adjust Smart Bidding until tracking is fixed. Let Google’s algorithm work with corrected data.
  6. Common root causes when this alert fires:
    • GTM container update breaking the conversion event tag (most common)
    • BC theme/checkout customisation breaking the purchase event firing
    • Conversion linker disabled or expired
    • Cookie consent changes (gtag consent mode v2 misconfigured)
    • Cross-domain tracking broken (referrer exclusion list outdated)
    • Apple ITP / browser blocking (gradual; usually flagged separately)
The diagnostic flow:
  1. See the alert. Compare Google Ads conversions vs BC total_orders.
  2. If BC orders unchanged: tracking issue. Investigate GTM, conversion linker, cookie consent.
  3. If BC orders also dropped: real demand event. Investigate site speed, OOS, paid spend changes.
  4. Fix the cause; re-train bidding.
Rapid-response playbook:
Time horizonAction
First 1 hourCross-check BC orders; confirm tracking vs demand.
First dayIdentify GTM / consent / tag root cause; fix.
First weekSmart Bidding re-trains; conversion data recovers.
Day 14Confirm performance returned to baseline.

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Sibling cards merchants should reference together

CardWhy merchants reach for it
gads_total_revenueRevenue companion.
gads_total_spendSpend; should track conversions.
gads_roasROAS; collapses when tracking breaks.
gads_alert_conversion_tracking_brokenMore specific tracking-broken alert.
total_ordersBC-side ground truth for cross-check.
ga4_alert_conversion_dropGA4-side companion alert.

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Reconciling against the vendor’s own dashboard

Where to look in Google Ads: Tools → Conversions; Diagnostic insights for tracking issues. Why our alert may differ from Google’s own:
ReasonDirectionWhat to do
Threshold sensitivity. Google’s alert may use 30%+ drops; this card alerts earlier at 15-25%.Vortex IQ earliern/a; earlier is better.
Per-campaign vs account-wide. Google may flag per-campaign; this card is account-wide.VariableCross-reference.
Data delay. Conversions report with up to 72-hour delay in some cases.VariableAllow 72h before treating recent drops as real.
Quick rule: always cross-check BC total_orders before assuming the alert is a real demand event.

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Known limitations / merchant FAQs

Q: The alert fired but BC orders are normal. What does that mean? Tracking is broken. The conversions are happening; Google Ads just can’t see them. Most common cause: a GTM container change broke the conversion event tag. Check GTM changelog, fix the tag, use Conversion Adjustments to backfill if possible. Q: The alert fired and BC orders also dropped. What does that mean? Real demand event. Investigate: site speed regression, OOS bestsellers, payment failure, deliverability issue, competitive event. Cross-reference psi_perf_score_summary, out_of_stock_count, failed_orders_trend. Q: We just upgraded our checkout app. Could that be the cause? Very likely. Checkout customisations frequently break the BC → GTM → Google Ads conversion chain. Test the new checkout in incognito and verify the purchase event fires in browser console. If it doesn’t, the new checkout app needs configuration to fire the event. Q: Should I pause campaigns while diagnosing? Generally no. Pausing kills bid history; resuming starts from cold and may take 2-4 weeks to recover. Better: keep campaigns running while you fix tracking; Smart Bidding will re-train on corrected data within 7-14 days. Q: Why is the threshold at -15% and not stricter? -15% over a week is the boundary between “natural variance” and “real signal”. Setting tighter (e.g., -10%) creates alert fatigue from weekend-vs-weekday or seasonal noise. The 24-hour sub-window at -25% catches the urgent cases. Q: We use offline conversions (in-store sales reported via API). Are those covered? Yes if uploaded via the standard offline conversion API and configured as conversion goals. The card monitors all conversions Google Ads counts, regardless of online or offline source. Q: Conversion adjustments, how do they work? After fixing tracking, you can upload corrected conversion data via Google Ads’ Conversion Adjustment API. This back-fills the missed conversions and updates Smart Bidding. Most agencies miss this step; it’s worth doing for any multi-day tracking outage. Q: How is this different from gads_alert_conversion_tracking_broken? This card is the broad conversion drop alert (which includes tracking failures and real demand drops). The other card is a specific tracking-failure detection that triggers on patterns like sudden zero-conversions in active campaigns. Both can fire together; this card fires on more scenarios.

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Tracked live in Vortex IQ Nerve Centre

Conversion Drop Alert is one of hundreds of KPI pulses Vortex IQ tracks across Google Ads and 70+ other ecommerce connectors. Nerve Centre runs the detection layer; Vortex Mind investigates the cause when something moves; Ask Viq lets you interrogate any number in plain English. Start for free or book a demo to see this metric running on your own data.