Metrics · Channel · Weekly · % · Updated 2026-07-21

What is Email Open Rate?

Short answer: The percentage of delivered emails that were opened by recipients.

Definition

The percentage of delivered emails that were opened by recipients.

Formula

Emails opened / Emails delivered x 100

How to measure

Divide the count of unique opens tracked by the email platform by the number of successfully delivered emails.

Why track it

Open rate is the first checkpoint for email effectiveness; a low rate points to a subject line or list quality problem before content even matters.

Example

A newsletter delivered to 10,000 subscribers with 3,200 opens reports a 32% open rate.

FAQ

What is Email Open Rate?
The percentage of delivered emails that were opened by recipients.
How do you calculate Email Open Rate?
Emails opened / Emails delivered x 100
Why track Email Open Rate?
Open rate is the first checkpoint for email effectiveness; a low rate points to a subject line or list quality problem before content even matters.
What is Email Open Rate? Definition, formula, and growth use · Cofounderbase