Marketing calculators
Email Open Rate Calculator
Calculate unique opens as a share of delivered emails after bounces. Your inputs stay in this browser.
Live calculator
Enter your numbers
What this calculator measures
Open rate divides unique opens by estimated delivered emails, which are sent emails minus bounces.
Formula
Open Rate % = Unique Opens / (Emails Sent - Bounces) x 100
Inputs and variables
- Unique opens
- Enter the value used by this formula.
- Emails sent
- Enter the value used by this formula.
- Bounces
- Enter the value used by this formula.
How to use the calculator
- Choose a display currency when money fields are present.
- Enter values that cover the same period, scope, and currency.
- Review the result, formula, and worked example before using the estimate in a decision.
- Change one assumption at a time to understand what drives the result.
Worked example
- 12,000 sends minus 200 bounces gives 1,800 delivered.
- 2360 unique opens / 1,800 x 100 = 20%.
How to interpret the result
Privacy protections and image loading can distort open tracking, so combine it with clicks and downstream outcomes.
Common mistakes and limits
- Using total opens, forgetting bounces, or comparing providers with different tracking behavior.
Frequently asked questions
Why use unique opens?
They reduce repeat opens by the same recipient.
Are opens exact?
No. Client privacy and image handling affect detection.
What if bounces equal sends?
There is no delivered denominator, so the rate is undefined.