Conversion Lag Report
Shows how long conversions take to arrive after the click — the distribution that explains why 'last week looks terrible' every week, and how much your recent CPA is understated.
by Dmytro Tonkikh·chiliad.io
Overview
Conversions are reported on the click date, so recent periods always look worse than they'll end up — the only question is by how much. Conversion Lag Report builds the distribution of days-between-click-and-conversion for your account, with cumulative percentages and a practical summary: what share arrives same-day, within 7 days, and later. That last number is exactly how understated last week's CPA is — the discount to apply before judging any recent change or panicking at a weekly report.
Setup
- 1Open your Google Ads account and go to Tools → Bulk Actions → Scripts.
- 2Click the + button to create a new script and paste the code below.
- 3Keep DATE_RANGE long (LAST_90_DAYS) — lag distributions need volume to be stable.
- 4Set EMAIL_ADDRESS to receive the report; leave blank for logs only.
- 5Preview once to verify, then schedule monthly.
Configuration Variables
| Variable | Default |
|---|---|
DATE_RANGE | LAST_90_DAYS |
EMAIL_ADDRESS | (empty) |
Expected Output
=== Conversion Lag Report (LAST_90_DAYS) === Conversions with lag data: 842.0 same day: 46.2% (cumulative: 46.2%) 1-2 days: 12.8% (cumulative: 59.0%) 2-3 days: 7.4% (cumulative: 66.4%) 6-7 days: 3.1% (cumulative: 78.9%) 14-21 days: 6.2% (cumulative: 91.4%) 21-30 days: 4.8% (cumulative: 96.2%) Same-day share: 46%. Within 7 days: 79%. Arriving later than 7 days: 21%. Practical reading: CPA for the last 7 days is understated by roughly 21% - judge recent changes with that discount in mind. Email sent to you@example.com
Notes
Uses all-conversions with Google's lag buckets. Different conversion actions have different lags — for a per-action view, add a conversion action filter and run per action. The direct applications: honest recency judgments, conversion window choices, and patience windows after Smart Bidding changes.