Name the stalled decision first
Write the decision you cannot make confidently right now — scale Meta or hold, whether TikTok is paying its way, which campaign to cut. The number you need is the one that unblocks this decision.
One number per spend decision.
When Meta, Google, and Shopify report different revenue, the spend decision stalls. This one-page spec gets you to one reconciled number you can fund decisions on — built backward from the decision that is stuck, then only the data that decision needs.
Five steps to one number.
List the tools that disagree
Put each tool’s answer in its own row — Meta, Google, TikTok, Shopify, GA4 — with how each one attributes. The spread between them is the problem; the goal is to reconcile them into one view.
Fix the tagging before you trust the numbers
Lowercase, no spaces, a fixed vocabulary for source and medium, every paid link tagged, one convention everyone uses. Below ~80% UTM coverage, your channel view is guesswork.
Define the one number (and its limits)
For the decision in step 01, write the single metric you will fund on — its source, formula, and where it under- or over-counts. The honesty about limits is what makes it trustworthy.
The decision-ready view
One screen: blended truth (revenue, spend, MER, CAC, AOV), platform-reported vs. reconciled with the delta visible, and the trend that matters. If you can answer "which channel and campaign earned its spend?" unaided, you are done.
Tell me what you wish existed.
The form routes to what fits, or captures your need if nothing here does yet.