Blog
Email Deliverability Guides & Best Practices
Guides, best practices, and intelligence from the InboxEagle team to help you land in the inbox every time.
Automation8 min
How to Improve Inbox Placement in Klaviyo Flows vs. Campaigns
Flows and campaigns behave differently in Klaviyo, and mailbox providers treat them differently too. Here's how to optimize inbox placement for each.
Analytics9 min
Spam Complaint Rate: What Every eCommerce Store Owner Needs to Know (2026)
Spam complaint rate is the metric Gmail uses to decide if your emails reach the inbox — and your Klaviyo dashboard isn't showing you the real number. Here's how to check it, what drives it up, and how to recover.
Analytics8 min
Email Blacklists: What They Are, How You Get Listed, and How to Get Off (2026)
An email blacklist can silently block your campaigns before a single recipient sees them. Here's what blacklists are, the exact behaviors that trigger a listing, how to run a free email blacklist check, and how to get removed.
Klaviyo11 min
Klaviyo + InboxEagle: How to Monitor Every Flow and Campaign
The Klaviyo InboxEagle integration gives you actual inbox placement data alongside Klaviyo's engagement metrics. This guide covers Private API Key setup, webhook configuration, analytics dashboards, and the monitoring workflow.
Analytics8 min
Do Spam Trigger Words Really Cause Spam? 774K Emails Tested
Do spam trigger words like 'free' and 'sale' actually send emails to spam? We analyzed 774,828 emails from Q1 2026. The findings may surprise you.
Analytics9 min
How to Check Your Email Sender Reputation Score
Your sender reputation score determines inbox or spam — before you hit send. Here's how to check it for free across Gmail, Outlook, and enterprise infrastructure, and what to do when the numbers are bad.
E-commerce7 min
Email Sunset Policy: The Data Behind a 3× Spam Rate Gap
InboxEagle analyzed 16,356 ecommerce senders. Low-volume programs average a 56% spam rate. High-volume programs average 18%. The difference is a sunset policy.
Klaviyo9 min
Klaviyo Suppression Lists: How to Use Them to Protect Deliverability
Klaviyo suppression list: five suppression types, global vs. list-level scope, what can be reversed, the billing distinction most brands miss, and how to use it to actively protect inbox placement.
Authentication5 min
Email Authentication for Klaviyo Senders: The Complete Guide
Email authentication is the foundation of inbox placement for every Klaviyo sender. Here's what SPF, DKIM, and DMARC actually do, why Klaviyo's default setup breaks DMARC alignment, and where to go deeper on each.
E-commerce8 min
Email Deliverability for Agencies: How to Manage Multiple Client Domains
Managing email deliverability across multiple client domains is one of the hardest operational challenges in eCommerce agency work. Here's the framework — domain isolation, monitoring at scale, and the mistakes that cause one client to hurt another.
E-commerce8 min
Email List Hygiene: The Deliverability Practice Most eCommerce Brands Skip
Email list hygiene is one of the highest-leverage deliverability practices for eCommerce brands — yet most skip it until a crisis forces their hand. Here's exactly what it is, why it matters, and how to diagnose and fix list decay in Klaviyo.
Authentication6 min
Why Your "Mailed-By" Domain Matters for Brand Trust
82.8% of marketing emails display a third-party mailed-by domain in Gmail. Here's what that signals to your subscribers and why it's quietly costing you deliverability equity.