Newsletter Open Rate & Click-To-Open Rate (CTOR) Auditor for 2026

Audit your newsletter open rate, CTR, and click-to-open rate against industry benchmarks. Identify content engagement gaps and optimize email performance.

Mathematical Audit

How Open Rate, CTR, and CTOR Are Calculated

These three metrics measure different aspects of email engagement — reach, overall click performance, and content relevance among readers.

Open Rate = (Unique Opens / Emails Delivered) × 100
Click-Through Rate (CTR) = (Unique Clicks / Emails Delivered) × 100
Click-To-Open Rate (CTOR) = (Unique Clicks / Unique Opens) × 100
Bounce Rate = (Bounced Emails / Emails Sent) × 100
Effective Delivery Rate = (Emails Delivered / Emails Sent) × 100

Apple Mail Privacy Protection (iOS 15+) inflates open rates by pre-loading tracking pixels. CTOR is now considered the more reliable engagement metric since it only measures behavior among confirmed openers.

Operational Guide

How to Use the Newsletter Open Rate & CTOR Auditor

1

Enter emails sent and delivered

Input the total number of emails sent and how many were successfully delivered to inboxes. The difference reveals your bounce rate.

2

Add unique opens

Enter the number of unique subscribers who opened your email. This data is available in your ESP analytics dashboard.

3

Add unique clicks

Enter the total unique clicks on links within your email. This measures how many readers took action.

4

Select your industry

Choose your newsletter industry to compare your metrics against relevant benchmarks.

5

Review your audit results

See your open rate, CTR, and CTOR with color-coded benchmark comparisons showing whether you're above or below industry average.

Real-World Scenario Example

"A tech newsletter sends 10,000 emails with 9,800 delivered, 2,500 unique opens, and 200 unique clicks."

Inputs

emailsSent:10000
emailsDelivered:9800
uniqueOpens:2500
uniqueClicks:200

Result

Open rate of 25.5%, CTR of 2.04%, and CTOR of 8.0%. The open rate is above the tech industry average of 22%, while the CTOR is slightly below the 10.5% benchmark.

Important Disclaimer

These audit results are based on the data you provide and industry-average benchmarks. Actual performance varies by audience, content type, and email service provider. Apple MPP may inflate open rate metrics.

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Sources & References

Mailchimp — Email Marketing Benchmarks & Industry Statistics

https://mailchimp.com/resources/email-marketing-benchmarks/

Campaign Monitor — What Are Good Email Metrics?

https://www.campaignmonitor.com/resources/knowledge-base/what-are-good-email-metrics/