Calculate your email campaign fatigue score and optimal sending frequency. Analyze open rate decline, unsubscribe pressure, and complaint signals to protect your sender reputation and audience engagement.
Campaign fatigue is measured by combining signals of audience exhaustion: open rate decline, unsubscribe pressure, spam complaints, and email frequency. A composite fatigue score (0-100) classifies your audience's tolerance level.
Enter your current sending frequency and engagement metrics to calculate your campaign fatigue score.
Get our guide to finding the optimal email cadence, reducing fatigue, and re-engaging lapsed subscribers.
Email campaign fatigue occurs when an audience receives too many emails in too short a period, leading to declining open rates, increased unsubscribes, and spam complaints. Understanding and managing fatigue is critical for protecting long-term email channel health and sender reputation.
Example 1: High Fatigue Scenario
Frequency: 5/week | Previous Open Rate: 28% | Current Open Rate: 16% (-43% decline)
Unsubscribe Rate: 1.2% | Complaint Rate: 0.18% — Fatigue Score: 78/100 (Critical)
Example 2: Healthy Cadence
Frequency: 1/week | Previous Open Rate: 22% | Current Open Rate: 21%
Unsubscribe Rate: 0.2% | Complaint Rate: 0.03% — Fatigue Score: 12/100 (Healthy)
Recovery steps: immediately reduce sending frequency by 50%, send a re-permission campaign to inactive subscribers, segment your list to send high-frequency only to highly-engaged subscribers, improve content quality and personalization, test different send times, and implement a preference center where subscribers choose their cadence.
How many emails per week is too many?
For most B2B audiences, 1-2 emails per week is optimal. Consumer brands can often send 3-5 per week to active buyers. Pharma HCP communications targeting physicians should be limited to 1-2 per week maximum, with clear differentiation between types (clinical data vs. program invitations).
How much open rate decline signals fatigue?
A decline of more than 20% over 4-8 weeks is a clear fatigue signal. A 30%+ decline requires immediate action. Some decline is normal from email to email, but a consistent downward trend across multiple sends indicates systemic fatigue rather than one-off performance variation.
What is the best way to prevent campaign fatigue?
Prevention strategies: implement a global frequency cap (max N emails per week per subscriber across all campaigns), build an engagement-based segmentation model (high-frequency only for highly-engaged), use preference centers, monitor fatigue metrics weekly, and ensure each email has clear, distinctive value for the recipient.