# Best tools for identifying and resolving spam filter issues?

<p class="elv-tracking-normal elv-text-default elv-font-figtree elv-text-base elv-leading-base elv-font-normal" elv="true">Hi all,</p><p class="elv-tracking-normal elv-text-default elv-font-figtree elv-text-base elv-leading-base elv-font-normal" elv="true">I’m helping a few growth and outreach teams troubleshoot <strong>why legitimate emails still end up in spam folders</strong>. So, I turned to<a class="a a--md" elv="true" href="https://www.g2.com/categories/email-deliverability"> </a><a class="a a--md" elv="true" href="https://www.g2.com/categories/email-deliverability">G2 data for Email Deliverability Tools</a> to identify tools that detect and fix spam filter triggers effectively.</p><p class="elv-tracking-normal elv-text-default elv-font-figtree elv-text-base elv-leading-base elv-font-normal" elv="true">Here are the top performers:</p><ul>
<li>
<a class="a a--md" elv="true" href="https://www.g2.com/products/constant-contact/reviews"><strong>Constant Contact</strong></a> – Best for automatically flagging content and domain issues that hurt inboxing.</li>
<li>
<a class="a a--md" elv="true" href="https://www.g2.com/products/instantly/reviews"><strong>Instantly</strong></a> – Best for diagnosing spam triggers in cold outreach sequences.</li>
<li>
<a class="a a--md" elv="true" href="https://www.g2.com/products/apollo-io/reviews"><strong>Apollo.io</strong></a> – Best for identifying low-reputation domains impacting outreach performance.</li>
<li>
<a class="a a--md" elv="true" href="https://www.g2.com/products/dotdigital/reviews"><strong>Dotdigital</strong></a> – Best for analyzing global deliverability issues and compliance risks.</li>
<li>
<a class="a a--md" elv="true" href="https://www.g2.com/products/brevo/reviews"><strong>Brevo Marketing Platform</strong></a> – Best for resolving content-based spam triggers and sender domain issues.</li>
</ul><p class="elv-tracking-normal elv-text-default elv-font-figtree elv-text-base elv-leading-base elv-font-normal" elv="true">Anyone using these tools? What's been your experience? Any other tools you recommend adding here?</p>

##### Post Metadata
- Posted at: 7 months ago
- Author title: SaaS and Software Research
- Net upvotes: 2


## Comments
### Comment 1

The most effective approach for us has been a combination of:

proper domain setup and authentication
gradual warm-up and consistent sending
improving list quality and targeting
adjusting content to avoid obvious spam triggers

The tools are helpful for diagnosing issues, but the real work happens in how you adjust your sending strategy.

##### Comment Metadata
- Posted at: about 1 month ago



### Comment 2

On the strategy question, we almost always start with authentication and domain health first (SPF, DKIM, DMARC, domain age, sending patterns). Content tweaks help, but if the domain reputation is weak, nothing really fixes it long-term.

##### Comment Metadata
- Posted at: about 1 month ago



### Comment 3

One thing we learned is that spam issues often come from sending behavior, not just email content. Sudden spikes in volume or inconsistent sending patterns can cause problems even with good copy.

##### Comment Metadata
- Posted at: about 1 month ago



### Comment 4

Here are my thoughts on this: From what we’ve seen, spam filtering issues are rarely caused by just one thing. Tools like Instantly, Brevo, or Constant Contact can help identify potential problems, whether it’s content, domain setup, or engagement patterns. But fixing those issues requires a combination of changes. For example, content-based tools can flag spammy language, but if your domain reputation is low or your sending patterns are inconsistent, you’ll still end up in spam. Similarly, domain-focused tools can help identify reputation issues, but they don’t solve problems related to poor targeting or low engagement.

##### Comment Metadata
- Posted at: about 1 month ago
- Author title: Marketing Executive



### Comment 5

&lt;p&gt;&lt;span style=&quot;background-color: transparent; color: rgb(0, 0, 0);&quot;&gt;&amp;nbsp;What’s been your go-to strategy when emails start landing in spam — domain rotation, content rework, or authentication fixes?&lt;/span&gt;&lt;/p&gt;

##### Comment Metadata
- Posted at: 7 months ago
- Author title: SaaS and Software Research





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