The 10 KPIs every conversion copywriter needs to track

Executive overview

Most copywriters avoid analytics, but without the right metrics you cannot prove your copy works. A handful of KPIs — split between email and web — give you everything you need to measure copy effectiveness and demonstrate results to clients.

Pick the key metrics, not all metrics. More data creates noise, not better decisions.

The dashboard analogy: your job is to watch the right gauges, not every gauge.

Email KPIs

1. Unique open rate — percentage of delivered emails opened by each recipient once. Industry average is 21.33% (Mailchimp, 2019). Measures subject line effectiveness.
2. Click-through rate (CTR) — percentage of delivered emails where at least one link was clicked. Industry average is 2.62%. Measures call-to-action effectiveness. Note: figures above 10% usually mean clicks are measured against opens, not deliveries.
3. Conversion rate — percentage of delivered emails that resulted in a sale, sign-up, or share. Measures end-to-end message effectiveness. Calculation methods vary — always ask how it is defined.
4. Average sales price (ASP) — total revenue divided by number of conversions. Reveals whether copy is driving the right product mix, not just volume. No industry average; benchmark against your own baseline.
5. Click-to-open rate — clicks as a percentage of opens (derived metric). Useful for isolating body-copy and CTA performance from subject-line effects.

Web KPIs

6. Traffic (sessions/unique visitors) — counts site visits. Unique visitors are preferred but can be inflated by cookie expiry or cleared cookies. Watch for traffic lifts after emails, ads, or SEO changes.
7. Time on site (average session duration) — two to three minutes is a healthy baseline; under one minute signals an engagement problem. Minimum needed to complete a checkout flow.
8. Pages per session — higher numbers generally indicate content engagement, but only meaningful if they correlate with conversions.
9. Bounce rate — percentage of visitors who leave after viewing only one page. High bounce rate plus low time on site is a strong engagement-issue indicator. Industry benchmarks range 25–75%, so compare against your own history.
10. Conversion rate and ASP (web) — same concepts as email but attributed across all channels, not a single campaign. If metrics look strong but sales are missing, check for technical issues (broken buttons, unsupported shipping regions) before revisiting copy.

Reading the data: learning over winning

• Two emails with identical conversion counts can have very different effectiveness — open rate, CTR, and ASP together tell the full story.
• Results that are statistically too close to call are not failures; they are learning opportunities about what each element did.
• Drill down when a top-line metric flags a problem: a high overall bounce rate may hide two underperforming channels among seven healthy ones.
• Copy is not always the culprit when conversions are low — rule out technical issues first.

Where to find these metrics in Google Analytics

• Audience overview: traffic, time on site, pages per session, bounce rate.
• Acquisition overview: channel-level breakdown and conversion data.
• Conversion metrics sit across multiple sections — not in a single report.