Marketing & Ecommerce

Email Open Rate Calculator

What this does

Measure email open rate, click rate and click-to-open rate from delivered counts, opens and clicks.

Enter your details

Runs in your browser

Calculator inputs

How to use it

Using the email open rate calculator

  1. 01

    Start from delivered, not sent

    Bounced addresses never saw anything, so honest rates use delivered as the denominator.

  2. 02

    Use unique counts

    One person opening five times counts once here; most platforms report both; pick uniques.

  3. 03

    Read all three together

    Strong opens with weak CTOR means subjects oversell the content; weak opens shift attention to deliverability and timing first.

Good to know

The Apple Mail open problem

Since Mail Privacy Protection, Apple prefetches images for users who never looked, inflating opens. Treat open rate as directional and weight click-based numbers; which require genuine intent; far more heavily.

CTOR separates subject from story

When open rate holds but click-to-open falls, recipients were hooked by the subject then let down inside. The fix is content relevance, not another subject-line experiment.

List hygiene beats cleverness

Engagement decays as lists age. Regularly sunsetting non-openers lifts every metric here, protects sender reputation, and paradoxically raises absolute revenue per send.

How it's calculated

The math behind this calculator

Open rate = opens ÷ delivered Click rate = clicks ÷ delivered Click-to-open rate = clicks ÷ opens

Three complementary views: open rate measures subject-line pull against everything delivered; click rate measures overall action against delivery; click-to-open isolates content effectiveness among people who actually looked.

Assumptions & limitations

  • Unique per-person counts, not raw total opens and clicks.
  • Delivered excludes bounces but includes privacy-inflated opens.
  • Apple Mail privacy prefetching can inflate open figures materially.

Worked example

Of 2,000 delivered emails, 450 opens make a 22.5% open rate; 90 clicks yield a 4.5% click rate and a 20% click-to-open rate among openers.

FAQ

Frequently asked questions

What is a good open rate?
Roughly 17–28% covers typical cross-industry medians, though it varies by list quality and audience. Trend against your own sends; Apple inflation makes cross-company comparisons unreliable now.
Why do opens exceed clicks so dramatically?
Opening takes curiosity; clicking takes motive. Click-to-open rates of 10–20% are normal, and 20%+ signals genuinely aligned message-market fit.
Should I A/B test subject lines?
Yes; they remain the largest single lever on opens. Just confirm any winner also sustains clicks, since curiosity-gap subjects often win opens and lose downstream engagement.

Keep exploring

Related calculators