Knowledge collection
Benchmarks
Benchmarks help an email team put its own measurements in context. Start with the newsletter open-rate guide to compare sources, data periods, audiences and methods. A recorded open may include Apple privacy activity, so the same dashboard number can describe very different audiences. Move to the unsubscribe, complaint and bounce guide for the denominators and thresholds that determine when a program needs review. The inactivity-cost article then connects contact states with the dated platform rates behind a budget estimate.
Use the calculator for a scenario, with assumptions visible, and the Dormant List Index for the definitions and publication rules that future editions must meet. The healthcare evidence review keeps peer-reviewed reminder findings separate from vendor claims. These pages provide reference ranges and measurement methods; a published average is not a target for every list. Keep your own cohort, consent records and sending history attached to any comparison, and use the original sources when reviewing a specific account.
Start with the collection pillar.
Dormant Email List Value Calculator: How Much Revenue Is Asleep in Your List (and What It Costs to Keep)
Estimate dormant email list value over 12 months. Share inputs, compare recovery scenarios and see the formula and platform billing rules.
Newsletter Open Rate Benchmarks 2027 by Industry and Platform (with the Apple MPP Caveat)
Open rate benchmarks from six 2024–2026 datasets: medians by industry, platform and list size, why they disagree, and the Apple MPP correction to apply.
What an Inactive Subscriber Costs You: Klaviyo vs beehiiv vs Mailchimp vs HubSpot Pricing Math (2026)
Which email platforms bill inactive or unsubscribed contacts, with 2026 prices for Klaviyo, beehiiv, Mailchimp and HubSpot and a worked example at 50,000.
Email Unsubscribe, Spam Complaint and Bounce Rate Benchmarks: Healthy, Warning, Critical
Healthy, warning and critical thresholds for unsubscribe, spam complaint and bounce rates: Gmail's 0.1% and 0.3%, Yahoo, SNDS, and 2023–2025 medians.
The Dormant List Index: Methodology, Definitions and Publication Rules
How EngageMKTG's Dormant List Index measures dormant, invalid and trap-pattern shares and reactivation rates from anonymized audits: definitions and rules.
No-Show Rates and What Reminders Really Change: An Evidence Review for Practice and Engagement Teams
What research says about patient no-shows: the 23% average from 105 studies, Cochrane's reminder evidence, MGMA's 2025–2026 polls, and vendor claims.