Blog
Email Deliverability Guides & Best Practices
Guides, best practices, and intelligence from the InboxEagle team to help you land in the inbox every time.
Authentication11 min
12 Email Marketing Mistakes Killing Your Deliverability in 2026
Sending but not landing? These 12 email marketing mistakes — from skipped authentication to bought lists — are the most common reasons emails go to spam. Learn what to fix.
E-commerce6 min
What Is a Sending Domain and Why Does It Need Its Own Reputation?
Your sending domain is the identity your email program lives or dies by — and it's separate from your website. Here's what it is, why it needs its own reputation, and what most Klaviyo senders get wrong about it.
E-commerce7 min
Email Domain Reputation: How It's Scored and How to Protect It
Email domain reputation is the primary signal ISPs use to route your campaigns. Here's exactly how it's scored, what damages it fastest, and how to protect it before the next send.
Gmail8 min
Gmail Promotions vs Spam: Where 671K Ecommerce Emails Landed
We measured Gmail placement for 671,329 emails across ~19,400 ecommerce senders in Q1 2026. Brand-level deliverability turns out to be close to binary — and the middle ground barely exists.
Analytics8 min
Dedicated IP vs. Shared IP for Email: What the Data Actually Shows
InboxEagle analyzed 15,174 IPs — 7,166 dedicated and 8,008 shared. Dedicated IPs had lower spam rates but lower Primary inbox. Here's why, and when a dedicated IP for email actually makes sense.
Authentication8 min
How Domain Alignment Affects Inbox Placement in 2026
Domain alignment is why your emails fail DMARC even with valid SPF and DKIM — here's what's breaking and how to fix it.
Authentication5 min
Does DMARC Failure Guarantee the Spam Folder? A 2M Email Study
We analyzed 2.2 million emails to find out if DMARC failure sends you straight to spam. The answer is more nuanced — and more actionable — than you'd expect.
Authentication6 min
The State of Email Authentication: SPF/DKIM Adoption in Ecommerce
Email authentication adoption in ecommerce leads every other industry — yet most brands still run DMARC at p=none. Here's what the 2025/2026 data says and where the real gap is.
Gmail7 min
Gmail Deliverability Benchmarks for Ecommerce Brands: Q1 2026 Data
InboxEagle monitored 721,351 emails to Gmail in Q1 2026. Here are the real gmail deliverability benchmarks — spam rates, tab placement, and what separates healthy programs from at-risk ones.
E-commerce6 min
The Ecommerce Email Deliverability Gap: What Top Brands Do Differently
InboxEagle analyzed 3,474 ecommerce sender domains and found a 72-point inbox placement gap between the best and worst performers. Here's the ecommerce email performance benchmark — and what separates top-quartile brands from everyone else.
E-commerce6 min
Do Aggressive Sale Subject Lines Hurt Deliverability? What Our Data Shows
Sale language doesn't automatically hurt deliverability — but some patterns do. InboxEagle analyzed 721,351 emails and found results that flip conventional wisdom on its head.
Authentication6 min
BIMI in 2026: Google's CMC Makes Brand Logos Affordable for Everyone
Google launched a Common Mark Certificate option for BIMI in 2025 — no trademark required. Here's how BIMI works, what's changed, and whether it's worth implementing for your email program.