8 Proven Tools to Improve Your Email Deliverability

Poor email deliverability kills campaigns. Emails lurking in spam or silently vanishing waste time, money, and energy. Teams lose trust in the process.

The good news: there’s a better way. Modern marketers use a toolbox of proven tools to test, optimize, and monitor every message. These tools catch technical issues, identify content risks, and track placement outcomes.

That ensures emails land in inboxes consistently. In this guide, I’ll walk you through eight top-rated email deliverability tools. You’ll learn what they do, how they work, and why each one matters.

By the end, you’ll be set to fix underlying issues, boost reputation, and reclaim your reach—no guesswork involved.

1. Mail-Tester.com

Mail?Tester.com is the Swiss army knife for quick spam diagnostics. Simply send a test email to the address provided. It replies with a score and a detailed analysis.

It checks items such as SPF, DKIM, DMARC alignment, header structure, spammy content, and blacklisted domains.

You get bullet-point insights pinpointing your weaknesses. Maybe your subject line is triggering filters. Maybe your DKIM signature is off. It tells all. It’s fast and free. Set it up before each campaign launch.

That way, you catch technical issues early, before they hurt your sender reputation. Over time, small fixes here add up. You’ll see better open rates and fewer rejections.

Mail-Tester offers a free spam testing tool for basic checks. Paid plans start at $19 for 5,000 test credits and go up to $139 for 10,000 credits. Credits don’t expire and can be used as needed.

2. GlockApps

GlockApps dives deeper than Mail-Tester. You send one test email. It shows results for Gmail, Outlook, Yahoo, and more. You learn if it went to the inbox or spam. You also get engagement stats—did it get opens or clicks?

It highlights issues like poor header setup or potentially risky links. It notifies you about blacklist status across dozens of sources.  

Your dashboard is intuitive. It shows patterns across campaigns. You can compare sends over time. This tool helps you refine your email infrastructure and content consistently.

You’ll catch issues like hidden blocklists or content triggers early, before they derail important campaigns. It gives you clarity and control.

GlockApps has a free plan that includes two email tests and 10,000 DMARC analytics credits. Paid plans begin at $49/month and scale up to $129/month for more tests and sending accounts. These plans include spam tests, inbox placement tracking, and DMARC monitoring.

3. InboxAlly

InboxAlly helps your messages bypass spam filters by building engagement value. It works by encouraging real people to open, reply, and engage with your emails. That tells mailbox providers you're trustworthy.

You’ll stop sending bulk messages blindly and rank higher with providers. InboxAlly also provides insights into how your sends are performing, including delivery trends, open rates, and engagement statistics.

If your domain has ever been listed on a blocklist, running an email blacklist check using InboxAlly ensures the tool operates from a clean slate.

This way, you're not just sending better emails—you’re sending them from a cleaner, more trusted source. The platform works well for marketers who’ve struggled with deliverability in the past and need a tool that goes beyond surface-level metrics.

It’s ideal for cold outreach or high-volume sends that need early reputational pushes. Instead of hoping for inbox placement, you actively earn it.

This tool helps maintain a high sender score. It’s simple, scalable, and targeted—helping you get results without compromises.

The Starter plan costs $149/month and supports 100 seed emails daily with one sender profile. The Plus plan is $645/month and supports up to 500 seed emails with five sender profiles. 

Premium plans are available for $1,190/month, offering more senders and advanced support.

4. MXToolbox

Blacklistings sneak up quietly and kill deliverability fast. MXToolbox helps you stay ahead. Use their email blacklist check tool to scan dozens of blocklists at once. It flags any IP or domain issues immediately.

It even tells you why you may have been listed. Perhaps old complaints, malware, or a misconfigured PTR record triggered it. MXToolbox then guides you through delisting steps.

Run checks weekly—or more often during high-volume campaigns. A clean blacklist report keeps mailbox providers trusting your domain. A single listing could wreck your entire campaign while you troubleshoot.

This tool keeps things visible and actionable. You know what’s wrong—and how to fix it—before your email program suffers.

MXToolbox allows one free monitor with 30 blacklist checks. The Delivery Center plan costs $129/month and includes inbox placement and complaint analysis. Their higher-tier Plus version is priced at $399/month for more advanced features.

5. Postmark’s Spam Check API

Postmark’s Spam Check API brings automation to troubleshooting. You plug your email draft into the API. You get instant spam score and feedback.

It highlights problem areas—like misleading subject lines, suspicious links, or malformed headers. It runs checks every time you update your draft. That saves you from sending risky campaigns by mistake.

It’s perfect for developers or teams automating newsletter systems. Instead of manually testing every send, you build quality control into the process.

Your emails launch clean and compliant. Over time, this maintains your sender reputation without effort. It’s like having a built-in deliverability QA station.

Postmark offers a free spam checker tool using SpamAssassin scoring. For email sending, pricing starts at $60.50/month for 50,000 emails. Higher tiers cost more based on volume, with $138/month covering 125,000 emails.

6. SendForensic

SendForensics takes a full-stack approach, encompassing content, infrastructure, reputation, and engagement. It simulates real-world inbox delivery across providers and geographies.

Its scoring breaks down into reputation, infrastructure, content quality, and engagement performance. It highlights issues such as list hygiene, low open rates, or trigger words.

It shows comparative benchmarks and gives clear recommendations. It’s ideal for teams who want granular insight and ongoing email health tracking.

You’ll restrict noisy subject lines, clean inactive subscribers, or update technical settings based on data. This tool helps you maintain deliverability even as campaigns evolve. You’ll build credibility with each batch you send.

The base plan is $49/month or $39/month when billed annually, supporting two domains and unlimited tests.

A $79/month tier adds support for five domains and more advanced reporting. Agency and Enterprise plans range from $199 to $349/month, with higher limits and team access.

7. Mailgun

Mailgun isn’t just a sending platform—it’s a full deliverability solution. Their analytics dashboard tracks bounce rates, spam complaints, open rates, and read retries. This gives you actionable insight from every campaign.

It also flags suspicious link behavior or domain issues in real time. You can segment by campaign, client, and period. That helps diagnose problems like a sudden drop in engagement or spikes in bounces.

It integrates with your sending API. That means you can trigger clean-up sequences or alerts programmatically. This is powerful for agencies, SaaS platforms, or high-volume campaigns that want continuous visibility and fast fixes, without manual reports.

Mailgun includes a free plan offering 100 emails per day with basic features. The Basic plan is $15/month for 10,000 emails, with higher tiers at $35/month and $90/month. Premium features include dedicated IPs, email validation, and analytics.

8. MailChimp’s Inbox Preview & Delivery Insights

MailChimp remains a favorite for smaller teams. Its Inbox Preview tool tests email rendering across devices and clients. You also receive Delivery Insights, including open rates, clicks, unsubscribes, and placement.

It warns you if your audience isn’t engaged or if subject lines are risky. It helps you remove inactive users before they damage your reputation.

That proactive cleaning keeps bounce rates low. It’s not powerhouse deliverability software, but for many small to mid-sized teams, it’s enough. You get routine checks, smart templates, and a good default setup.

If you’re launching seasonal campaigns, newsletters, or onboarding flows, MailChimp gives you safe, reliable deliverability with minimal fuss.

MailChimp’s free plan includes 500 contacts and 1,000 email sends per month. The Essentials plan starts at around $13 to $15/month for additional features and volume.

More advanced tiers like Standard and Premium cost $20/month and up to $350/month, respectively.

Use the Right Tools for Strategy

Picking the right email deliverability tools depends on your scale, budget, and workflow. Start with authentication tools and checklist audits. Add placement testing, such as GlockApps, for ongoing validation.

Integrate Postmark or SendForensics for proactive quality checks. Use InboxAlly to push your reputation higher through human engagement.

Monitor API analytics via Mailgun for trends. And never skip blacklist checks; you’ll be shut down if you get listed.

Stick to short sending windows. Schedule a list hygiene. Optimize your send times. This toolbox gives you layered protection and visibility.

No tool alone guarantees success. However, when used effectively, these tools provide you with data-driven confidence that every email matters.

The Bottom Line

Deliverability isn’t optional—it’s essential. Without it, your email program fails before it starts. Utilize tools such as blacklist checks, placement tests, engagement boosters, and analytics to stay sharp.

Each step protects you from downtime, flags, and missed campaigns. These eight tools offer full coverage. But even one can solve a recurring issue. The key is consistency. Deliverability won’t fix itself.

Make testing a routine. Track results. Troubleshoot early. Your inbox placement will steadily improve.

More inboxes mean more opens, click-throughs, and conversions. So, build your toolkit. Send with confidence. And make every email work harder.