📩 Stop Guessing, Start Testing

If you care about deliverability, treat Mail Tester like a preflight check. One minute now saves headaches later.

In partnership with

Shoppers are adding to cart for the holidays

Over the next year, Roku predicts that 100% of the streaming audience will see ads. For growth marketers in 2026, CTV will remain an important “safe space” as AI creates widespread disruption in the search and social channels. Plus, easier access to self-serve CTV ad buying tools and targeting options will lead to a surge in locally-targeted streaming campaigns.

Read our guide to find out why growth marketers should make sure CTV is part of their 2026 media mix.

Learn more.

What Mail Tester does
You send your email to a unique address, it runs a quick audit, then returns a score out of 10 with specific fixes. Think content flags, missing authentication, and formatting quirks that spam filters dislike. Scores above 9 are a solid target, not a guarantee, just a strong signal.

Five-minute workflow

1. Draft your email
   Write it in your platform of choice. Keep the voice yours, not canned. Avoid shouty subject lines and link shorteners if you can.

2. Grab the test address
   Open Mail Tester and copy the unique address it generates for you. It will look like [email protected].

3. Send the email to that address
   From your ESP, send the exact version you plan to ship. No placeholders. If you use Beehiiv, paste the address like any other recipient and hit send.

4. Check the score
   Back on Mail Tester, click Check your score. Wait a few seconds, then open the report.

5. Read the line-by-line notes
   Expand each item to see what went wrong and how to fix it. Common ones:

• Authentication: SPF, DKIM, or DMARC not set or misaligned.

• Content: spammy phrasing, too many images, or a skewed image-to-text ratio.

• Technical: broken links, missing plain-text part, or odd HTML.

6. Fix, resend, recheck
   Make the changes Mail Tester suggests, ask it for a fresh unique address, resend, and review the new score. Repeat until you are comfortable with the result.

74% of Companies Are Seeing ROI from AI.

Incomplete data wastes time and stalls ROI. Bright Data connects your AI to real-time public web data so you launch faster, make confident decisions, and achieve real business growth.

Get Access

*Ad

A few practical notes

• Aim high, stay calm
  A 9 or above is great. An 8 with clear, explainable tradeoffs can be fine if you understand the risks. Let the notes guide you, not the number alone.

• Test every send
  Templates drift. New links, different images, fresh copy, all of it can nudge filters. A quick run before each campaign keeps surprises out of your inbox placement.

• Fix the root causes
  If authentication keeps failing, talk to whoever manages your domain and align SPF, DKIM, and DMARC. One clean setup improves every future send.

By running this simple loop, you move from hope to evidence. Ship with confidence.

AI You’ll Actually Understand

Cut through the noise. The AI Report makes AI clear, practical, and useful—without needing a technical background.

Join 400,000+ professionals mastering AI in minutes a day.

Stay informed. Stay ahead.

No fluff—just results.

Smarter AI. Zero fluff.

*Ad