Click-Through Rate (Email)
The percentage of email recipients who click on one or more links within an email. It measures how effectively email content drives engagement and moves recipients toward a desired action. CTR is calculated by dividing unique clicks by total delivered emails and multiplying by 100. A related metric, click-to-open rate (CTOR), divides clicks by opens to isolate content effectiveness from subject line performance. Industry average email CTR is 2-3%, though triggered and transactional emails often achieve 5-8%.
Why It Matters
Email click-through rate measures whether your content motivates action beyond just opening the message. It reflects the relevance of your offer, the clarity of your call-to-action, and the overall quality of your email design and copy. Unlike open rate, CTR is unaffected by Apple Mail Privacy Protection, making it a more reliable metric in the post-iOS 15 era. Improving CTR by even 0.5 percentage points on a 100,000-subscriber list means 500 additional engaged prospects per campaign, which can translate directly to measurable revenue gains.
Example
A newsletter is sent to 20,000 subscribers with 5,000 opens (25% open rate). Of those who opened, 800 clicked a link, giving a 4% click-through rate. The top-performing link is a product recommendation personalized by past purchase history. The team tests a redesigned email with a single prominent CTA button versus the previous layout with six text links. The single-CTA version increases CTR from 4% to 6.2%, generating 440 additional clicks per campaign and a 35% lift in email-attributed revenue.
Related Terms
Email Open Rate
The percentage of email recipients who open a given email. It is a key indicator of subject line effectiveness and sender reputation, though tracking accuracy has declined significantly since Apple Mail Privacy Protection (iOS 15) began pre-loading tracking pixels in 2021. The formula is unique opens divided by delivered emails (excluding bounces) multiplied by 100. Industry average open rates range from 15-25% depending on sector, with nonprofit and government emails averaging highest at 28% and retail averaging around 18%.
Conversion Rate
The percentage of visitors who complete a desired action, such as making a purchase, signing up for a newsletter, or requesting a demo. It is calculated by dividing the number of conversions by total visitors and multiplying by 100. Conversion rate applies to any measurable goal, including micro-conversions like adding items to a cart and macro-conversions like completing a purchase. Industry benchmarks vary widely: e-commerce sites average 2-3%, while SaaS landing pages often target 5-10%.