E-commerce Measurement: Reading the Sales Funnel with GA4

A funnel you do not measure cannot be improved. With GA4 e-commerce events set up correctly, the conversion rate of every step becomes visible.

Required events

• view_item — product page
• add_to_cart
• begin_checkout
• add_payment_info
• purchase — with transaction ID and revenue

Setup principles

Send events through Google Tag Manager via the data layer; do not hard-code them in the theme. Server-side tagging reduces data loss from ad blockers. Feed the Meta Conversions API and Google Ads conversions from the same data layer.

Reporting

Use GA4 funnel exploration to follow drop-off step by step and compare conversion by source/medium. Allocate ad budget across channels on that data.