Email Open Rate Calculator: Opens as a Share of Delivered Emails
Work out your email open rate from opens and delivered emails — the classic engagement metric for newsletters and campaigns, with the unopened share shown alongside.
Adjust the inputs and select Calculate for a full breakdown.
Compare Common Scenarios
How the numbers shift across typical situations for this calculator:
| Scenario | Open rate | Not opened |
|---|---|---|
| 420 of 2,000 (21%) | 21.00% | 79.00% |
| 300 of 1,000 (30%) | 30.00% | 70.00% |
| 1,200 of 8,000 (15%) | 15.00% | 85.00% |
| 550 of 1,000 (55%, small engaged list) | 55.00% | 45.00% |
How This Calculator Works
Enter the number of opens and the number of delivered emails (sent minus bounces). The calculator divides one by the other and multiplies by 100 to give the open rate, with the unopened share next to it. Always use delivered, not sent, as the base for an accurate figure.
The Formula
Part as a Percentage of a Whole
Part is the portion, Whole is the total it belongs to
Worked Example
420 opens from 2,000 delivered emails is a 21% open rate, with 79% not opened. Average open rates vary by industry but commonly land in the 15%–30% range. Two important caveats: always calculate on delivered (not sent) emails so bounces don't distort the rate, and know that open tracking has become unreliable — Apple's Mail Privacy Protection pre-loads tracking pixels, automatically counting 'opens' that may not reflect a real read, which inflates open rates for audiences with many Apple Mail users.
Key Insight
Open rate used to be the headline email metric, but privacy changes have made it far less trustworthy, so treat it as a directional signal rather than gospel. Apple's Mail Privacy Protection (and similar features) pre-fetch the tracking pixel, registering opens that didn't happen — which can inflate open rates substantially and break historical comparisons. The practical response is to lean on metrics that survive these changes: click-through rate and clicks-to-delivered measure actual engagement, conversions tie email to revenue, and list health (unsubscribes, spam complaints, bounce rate) signals deliverability. If you do track opens, use them for relative trends within the same audience and tooling, segment heavily, and never optimize subject lines on open rate alone now that the number is polluted. The fundamentals still matter most: a clean, engaged list, a recognizable sender, relevant content, and good send timing drive both real opens and the clicks that actually count.
Open rate benchmarks (post-Apple MPP era)
OPEN RATE BENCHMARKS 2024 by sector (Mailchimp).
Government. 28-42%.
Nonprofit. 28-40%.
Religious organizations. 35-45%.
B2B. 22-32%.
B2C/Retail. 20-30%.
E-commerce. 17-27%.
Real estate. 25-35%.
Restaurants. 21-30%.
Travel/hospitality. 24-34%.
Substantial — most sectors 25-40% range 2024.
Substantial increase post-Apple MPP from pre-2021 baseline 18-22% industry-wide.
MPP INFLATION FACTOR.
Apple devices ~50% U.S. mobile email opens.
MPP pre-fetches images. Reports open even if user never views.
Substantial 25-50% inflation in reported open rate.
True engagement substantial lower than reported.
ALTERNATIVE METRICS replacing open rate.
(1) CLICK-THROUGH RATE (CTR). Click any link / delivered. 2-5% benchmark.
(2) CLICK-TO-OPEN RATE (CTOR). Click / open. 10-20% benchmark.
(3) CONVERSION RATE. Click → desired action.
(4) REVENUE PER EMAIL.
(5) REPLY RATE (especially B2B).
(6) UNSUBSCRIBE RATE. Inverse engagement signal.
(7) SPAM COMPLAINT RATE. Strong negative signal.
(8) ENGAGEMENT RECENCY (last open/click within 30/60/90 days).
Substantial — most ESPs now feature these primary metrics.
STRATEGIC IMPACT.
Substantial — pre-2021 open-rate-driven optimization (subject line testing) less effective.
Click-driven optimization substantial.
Substantial focus on offer + design + landing page (post-click).
Inbox placement diagnostic — ALPHA testing via Litmus, Inbox Monster.
Optimization tactics for click + conversion (post-MPP)
SUBJECT LINE optimization (still matters — clickers must open first).
Length. 30-50 chars typical mobile preview.
Personalization. First name modest lift.
Urgency/scarcity. Substantial — but used carefully.
Question form. Substantial click hooks.
Emoji. Substantial — sector dependent.
PREHEADER TEXT substantial — visible in inbox preview.
DESIGN.
Mobile-first (~60-70% opens mobile).
Single column substantial readability.
Clear CTA above fold.
Substantial bulletproof buttons (no images-required).
Dark mode considerations.
TIMING.
Send time substantial — sector dependent.
B2B. Tuesday-Thursday 9-11am, 1-3pm typical best.
B2C. Substantial variable. Sunday evenings, Tuesday mornings strong.
Substantial test for your audience.
SEGMENTATION.
Substantial. Send right message to right segment.
RFM segmentation (recency/frequency/monetary).
Behavior triggers (visited page X).
Lifecycle stage (new subscriber, active, lapsed).
PERSONALIZATION.
Substantial. Name, location, past purchase, browsing history.
Substantial lift CTR 20-50% well-personalized.
AUTOMATION.
Welcome series. Substantial.
Abandoned cart. Substantial.
Post-purchase. Substantial.
Re-engagement. Substantial dormant subscriber recovery.
Birthday / anniversary. Substantial.
A/B TESTING.
Subject line, send time, CTA, design.
Substantial statistical significance (substantial sample size).
LANDING PAGE OPTIMIZATION.
Email click → landing page conversion. Substantial. Match email promise.
Email open rate benchmarks 2024 (post-Apple MPP)
Reference open rates by sector (post-MPP inflated).
| Sector | Open rate | CTR target |
|---|---|---|
| Government | 28-42% | 2-3% |
| Nonprofit | 28-40% | 2-3% |
| Religious | 35-45% | 3-5% |
| B2B / SaaS | 22-32% | 2-4% |
| Retail / e-commerce | 17-30% | 1-3% |
| Real estate | 25-35% | 2-3% |
| Travel / hospitality | 24-34% | 2-4% |
| Restaurants | 21-30% | 1-3% |
| Education | 25-35% | 2-4% |
| Healthcare | 23-32% | 2-3% |
| Industry avg 2024 | ~25-30% | ~2-3% |
Apple MPP (iOS 15+ 2021) substantially inflated reported open rates 25-50%. True user engagement substantially below reported. Click-through rate (CTR), click-to-open rate (CTOR), conversion rate now primary engagement metrics. Mailchimp + Campaign Monitor + Litmus benchmark sources.
Frequently Asked Questions
How is email open rate calculated?
Divide opens by delivered emails, then multiply by 100. 420 opens from 2,000 delivered is a 21% open rate, with 79% not opened. Use delivered (sent minus bounces), not total sent, as the base.
Should I use sent or delivered as the base?
Delivered. Bounced emails were never received, so including them in the base understates your true open rate. Most email platforms report on delivered by default — calculating on delivered gives an accurate picture of how your reachable audience engaged.
What's a good email open rate?
It varies by industry, commonly 15%–30%, but benchmarks have become less meaningful since privacy features distort open tracking. Compare against your own historical rates within the same audience and tools rather than chasing a universal number.
When is this calculator unreliable?
Critically less reliable post-Apple MPP (iOS 15+ 2021) which pre-fetches all images including tracking pixels — substantially inflates Apple-domain opens to ~100%. Apple Mail ~50% mobile email share. Calculator returns mathematically correct rate, but interpretation must account for substantial MPP inflation. Click-through rate (CTR) now more reliable engagement metric. Use open rate primarily for relative trend analysis vs absolute benchmark.
What should I track instead?
Metrics that survive privacy changes: click-through rate and clicks-to-delivered (actual engagement), conversions (email's link to revenue), and list-health signals like unsubscribes, spam complaints, and bounce rate. These measure real interest and deliverability better than a polluted open rate.
References & Authoritative Sources
- Mailchimp — Email Marketing Benchmarks by Industry · consulted June 1, 2026 · Industry benchmark
- Litmus — State of Email Research · consulted June 1, 2026 · Email research
- Campaign Monitor — Email Marketing Statistics · consulted June 1, 2026 · Industry data
Related Calculators
Embed this calculator
Add this calculator to your website for your readers. The embed includes a neutral attribution link to the original CalcDomain page for methodology, updates, and source notes.
Attribution uses rel="nofollow" by default and is included for transparency, not ranking manipulation.
Suggest an improvement
Found a calculation issue, outdated source, unclear assumption, or missing edge case? Send a short note so we can review it.
Methodology & Review
Email open rate = (emails opened / emails delivered) × 100%. Industry benchmark 2024: 25-45% (substantial increase post-Apple MPP iOS 15 2021 which pre-fetches all Apple Mail messages). Apple-inflated open rate substantially overstates true engagement. Calculator returns open rate; user should interpret with MPP caveat. RELIABILITY: Reliable for ESP-reported open data. Critically less reliable post-Apple MPP (iOS 15+ 2021) which pre-fetches all images including tracking pixels — substantially inflates Apple-domain opens to ~100%. Apple Mail ~50% mobile share. Click rate now more reliable engagement metric. Open rate now used primarily for relative trend analysis vs absolute.
Reviewed according to the CalcDomain Editorial Policy & Calculator Methodology. We document formulas, edge cases, sources, update dates, and correction paths for calculator pages.
Updated