14 Best Email Deliverability Tools in 2025 [Expert Review]

Email deliverability tools are essential for success today. Imagine creating a perfect email—a great offer, a catchy subject line, and perfect timing—only to have it land silently in the spam folder. That is every marketer's worst nightmare. Even the best content is useless if no one sees it.

In 2025, reaching the Primary Inbox is harder than ever. Internet Service Providers (ISPs) like Gmail and Outlook use advanced AI to filter out noise. To beat them, you need more than just luck; you need the right software stack.

This guide covers the 14 best email deliverability tools on the market. We have analyzed the top contenders, including industry favorites and powerful new platforms, to give you a complete picture and help you guarantee your emails get seen.

What is Email Deliverability? (And Why You Should Care)

Email Delivery means your email reached the receiving server (it didn’t bounce).

Email Deliverability means your email actually landed in the Primary Inbox, not the Junk, Spam, or Promotions tab.

Key Factors That Affect Deliverability:

• Sender Reputation: Your "credit score" with ISPs. ‍
• Authentication: Proper setup of SPF, DKIM, and DMARC. ‍
• List Hygiene: Removing invalid emails and spam traps. ‍
• Engagement: Do people open and reply to your emails?

Top Email Deliverability Tools: The Complete List

We have categorized these tools by their primary strength: Testing, Warm-up, Monitoring, and Hygiene.

1. GlockApps

Best For: Detailed technical analysis and spam testing.

GlockApps is an industry veteran. It provides deep insight into why emails are failing and offers a comprehensive suite of tools for IT and marketing teams.

Key Features:

• Seed List Testing: Send a test email to a list of control accounts to see global deliverability rates. ‍
• DMARC Analyzer: Protects your domain from spoofing and phishing attacks. ‍
• Uptime Monitor: Alerts you if your website or sending IP goes down. ‍
• IP Reputation: Scans dozens of blacklists to ensure you aren't blocked.

Pros:

• Extremely detailed reports suitable for enterprise teams.
• Offers a "GlockApps Spam Score" that is highly respected.
• Integrates DMARC analytics directly into the dashboard.

Cons:

• Can be expensive for small teams or frequent testers.
• The interface can be overwhelming for beginners.

Pricing:

• Basic: Free (limited tests).
• Essential: Starts at $59/month.

2. TrulyInbox

Best For: Affordable, unlimited email warm-up.

TrulyInbox focuses on one specific problem: Sender Reputation. It simulates human interaction to "warm up" your email accounts, signaling to ISPs that you are a trustworthy sender. It stands out by offering unlimited account connections.

Key Features:

• Human-Like Interaction: Opens, reads, stars, and replies to emails automatically. ‍
• Smart Ramp-Up: Gradually increases sending volume to avoid triggering alarm bells with ISPs. ‍
• Spam Removal: Automatically moves your emails from the Spam folder to the Inbox (a huge trust signal). ‍
• Repo-Check: Monitors your domain and IP reputation constantly.

Pros:

• Unlimited Email Accounts: You can warm up as many inboxes as you want for one price.
• Very affordable compared to competitors.
• Simple, "set it and forget it" interface.
• Includes SpamAssassin content scoring.

Cons:

• Does not have advanced blacklist monitoring features.
• Focused purely on warm-up and placement, not deep technical analytics.

Pricing:

Flat Rate: $22/month (Annual plan).

3. Inbox Radar (by Saleshandy)

Best For: Automated inbox placement testing and finding spam triggers.

Inbox Radar is a standout tool because it takes the guesswork out of where your emails are landing. Unlike basic testers, it provides a "Pre-flight Check" for your campaigns, simulating how major providers like Gmail, Outlook, and Yahoo will treat your message before you actually send it.

Key Features:

• Inbox Placement Testing: See exactly where your email lands (Primary, Spam, or Promotions) across widely used ISPs. ‍
• Spam Trigger Detection: Highlights specific words or formatting in your content that might trigger spam filters. ‍
• Recurring Tests: Schedule automatic tests daily or weekly to monitor health without manual work. ‍
• DNS Monitoring: Alerts you instantly if your SPF, DKIM, or DMARC records break.

Pros:

• Tests across all major providers (Gmail, Outlook, Zoho, Yahoo).
• Visual reports that are easy to share with clients or teams.
• Real-time "SpamAssassin" scoring to fix content issues immediately.
• Built-in blacklist monitoring.

Cons:

• It is a paid add-on within the Saleshandy ecosystem (no free trial for this specific feature).

Pricing:

• Inbox Starter: $23/month. ‍
• Inbox Pro: $79/month.

4. Folderly

Best For: Actively fixing spam folder issues.

Folderly positions itself as a solution that "fixes" spam issues rather than just monitoring them. It uses a proprietary AI process to locate your emails in spam folders and interact with them to restore your reputation.

Key Features:

• Spam Fixer: actively repairs bad sender reputation by generating positive engagement. ‍
• Content Analysis: Deep dives into your HTML and copy to find "spammy" elements. ‍
• Deliverability Dashboard: A unified view of all your domains and their health scores.

Pros:

• High success rate for fixing "Outlook/Microsoft" spam filtering issues.
• User-friendly dashboard.
• Combines warm-up with active repair.

Cons:

• One of the more expensive options on the market.
• Pricing is per mailbox, which scales up costs quickly.

Pricing:

• Approx $120/month (Annual plan).

5. Smartlead

Best For: High-volume cold emailers and agencies.

Smartlead has become a favorite for agencies. This powerful email automation tool combines sending with high deliverability features. It lets you manage hundreds of client mailboxes. It automatically warms up their sender reputation at the same time.

Key Features:

• Unlimited Auto-Warmup: Built-in warm-up for every mailbox you connect. ‍
• Master Inbox: Manage replies from all accounts in one place. ‍
• Rotational Sending: Spreads your sending volume across multiple IPs/domains to protect reputation.

Pros:

• Incredible value for agencies (unlimited mailboxes).
• Strong focus on "cold email" deliverability nuances.
• API access for custom integrations.

Cons:

• Reporting is great for sending, but less detailed on "why" an email failed compared to GlockApps.

Pricing:

Starts at $39/month.

6. Postmark

Best For: Transactional email speed and reliability.

Postmark is different from the others. It is an email service provider (ESP) specifically built for transactional emails (password resets, receipts). They prioritize speed and have some of the strictest reputation standards in the industry.

Key Features:

• Lightning Fast Delivery: Optimized to deliver emails in under 1 second. ‍
• 45-Day History: Keeps a full log of every email sent and its status for 45 days. ‍
• Message Streams: Separates your "Marketing" mail from "Transactional" mail so one doesn't hurt the other.

Pros:

• Best-in-class delivery rates for application emails.
• Excellent developer documentation and API.
• Strict approval process keeps their shared IPs clean.

Cons:

• Not for bulk marketing or cold outreach (they will ban you).
• Strictly for transactional/application mail.

Pricing:

• Starts at $15/month for 10,000 emails.

7. InboxAlly

Best For: Repairing engagement and sender reputation.

InboxAlly is a powerhouse for senders who need to "teach" inbox providers to love their emails again. It is often used by affiliate marketers and high-volume senders.

Key Features:

• Engagement Generation: Uses real people to open, scroll, and click your emails. ‍
• Broadcasting Compatible: Works with any newsletter platform (Mailchimp, ActiveCampaign, etc.). ‍
• Placement Tracking: Tracks open rates across different providers.

Pros:

• Very effective at fixing "Promotions Tab" placement issues.
• Can rescue domains that have been blacklisted or penalized.
• Works with any ESP.

Cons:

• Premium pricing compared to simple warm-up tools.
• No email authentication features (DKIM/SPF checks).

Pricing:

• Starts at $149/month.

8. MxToolbox

Best For: IT professionals and quick diagnostic checks.

MxToolbox is the "Swiss Army Knife" of email deliverability. It is widely used to check if a domain is on a blacklist or if DNS records are set up correctly.

Key Features:

• Blacklist Check: Scans over 100+ global blacklists instantly. ‍
• SMTP Diagnostics: Tests your mail server to see if it is responding correctly. ‍
• Header Analyzer: Decodes email headers to find technical errors.

Pros:

• The free version is very useful for quick checks.
• Extremely accurate technical data.
• Trusted by IT professionals worldwide.

Cons:

• The interface is dated and technical.
• Doesn't provide "solutions" to fix the problems, just alerts.

Pricing:

• Free basic tools. Paid plans start at $129/month.

9. Google Postmaster Tools

Best For: Getting data directly from the source (Gmail).

If you send email to Gmail users (which is likely 50%+ of your list), you need this. It is the only way to see what Google officially thinks of your domain.

Key Features:

• Domain Reputation: Scores you as Bad, Low, Medium, or High. ‍
• Spam Rate: Shows the percentage of users marking you as spam. ‍
• Encryption Check: Verifies your emails are secure (TLS).

Pros:

• 100% Free.
• The most accurate data for Gmail deliverability.
• Essential for troubleshooting sudden drops in open rates.

Cons:

• Only works for Gmail; no data for Outlook or Yahoo.
• Data is delayed by 24 hours.

Pricing:

Free.

10. Mailtrap  

Best For: App builders, testers, and coders who need safe email checks.

Mailtrap does two things well. First, it is an Email Sandbox. This is a safe place to test emails. It stops test emails from going to real customers. Second, it is a full Email Sending Platform. It sends production emails. This tool is very valuable. It removes the risk of sending bad emails during the building stage.

Key Features:

• Email Sandbox (Fake SMTP): It catches test emails. It stops them from going out. ‍
• HTML/CSS Checker: It checks your email's code. It ensures it looks right on all phones and computers. ‍
• Spam Analysis: It gives you a SpamAssassin score. This flags bad content before you send it. ‍
• Deliverability Monitoring: It watches key numbers on its sending platform. It tracks opens and clicks. ‍
• Automated Warm-up: It slowly starts sending emails. This builds trust for new services.

Pros:

• It stops all risk of accidental emails during development.
• It has great tools for developers. You get detailed logs and secure access.
• Testing and sending are together in one platform.

Cons:

• The free plan limits how many test emails you can send. This limit can be reached fast.
• The best tools for deliverability are only for the full paid service.

Pricing:

• Email Sandbox: Free plan exists. Paid plans start at about $14.99 per month. ‍
• Email API/SMTP: Paid plans start at about $15 per month for 10,000 emails.

11. Mailgun Optimize (InboxReady)

Best For: High-volume senders, coders, and companies using Mailgun.

Mailgun has a great deliverability tool. It is called Optimize. It helps users fix problems with Mailgun's system. It gives deep, technical answers. This is key for sending emails at a large scale.

Key Features:

• Inbox Placement Testing: It shows where your email lands. This includes the Inbox, Spam, or Promotions folders. ‍
• Reputation Monitoring: It checks your domain and IP on blacklists. This stops spam traps. ‍
• Automated Warm-up: It guides you through warming up new dedicated IPs and domains. ‍
• Authentication Validation: It checks your SPF, DKIM, and DMARC settings. This must be right. ‍
• Engagement Metrics: It breaks down performance by email provider. This helps fix specific problems.

Pros:

• It works perfectly for people who already use Mailgun. Sending and fixing are in one place.
• It has strong tools for developers and API access.
• The service is reliable for all types of emails.

Cons:

• You often need a higher-priced plan to get the best tools.
• The look of the tool is very technical. It may confuse non-marketers.

Pricing:

Deliverability tools are often added to Foundation ($35 per month) or Scale ($90 per month) plans. They can also be purchased separately.

12. ZeroBounce

Best For: Any business that values a clean email list. It is vital for list health.

ZeroBounce is a top tool for cleaning lists. It is known for being very accurate. It promises to find almost all bad emails (98%+). It removes hard bounces, spam traps, and bad addresses before you send.

Key Features:

• 98%+ Email Verification: It cleans lists well. It finds good, fake, or harmful emails. ‍
• Spam Trap Detection: It finds hidden spam trap emails. This protects your sender score. ‍
• A.I. Email Scoring: It gives a quality score (0-10) to risky emails. This predicts if they will engage. ‍
• Deliverability Toolkit: This includes checking blacklists and DMARC. It also tests inbox placement. ‍
• Activity Data: It shows how recently an email address was active. This helps prioritize good leads.

Pros:

• This email verification tool promises the best accuracy. They back it up with a strong guarantee.
• You only pay when you use it. This is good for cleaning lists once in a while.
• It meets strict security rules like GDPR.

Cons:

• You must pay extra for the full deliverability tools.
• Cleaning very large lists can sometimes take a long time.

Pricing:

• Pay-As-You-Go: Starts at $18 for 2,000 credits. ‍
• Deliverability Tools (Subscription): Basic tools start at about $49 per month.

13. Everest (Validity)  

Best For: Huge companies, banks, and large corporations needing top security and trust.

Everest is a huge, detailed tool for deliverability. It is built for big companies. It mixes monitoring, testing, and spying on competitors. It includes Sender Certification. This is a special program that gives you VIP access to major email providers.

Key Features:

• Sender Certification: This paid program gives you near-guaranteed inbox landing. Top providers trust you. ‍
• Inbox Placement Insights: It uses the largest network to track where emails land. This data is very accurate. ‍
• Competitive Intelligence: You can see what your rivals are sending. You track their frequency and subject lines. ‍
• Reputation & DMARC Monitoring: It watches your sender score and checks for major blocks. ‍
• List Validation: It connects to their other tool, BriteVerify. This cleans your lists in real time.

Pros:

• It offers the highest possible inbox rates because of the Certification program.
• It has unmatched competitive data and engagement analysis.
• It works perfectly for huge, worldwide email programs.

Cons:

• It is extremely expensive. The full cost is only for very large organizations.
• Setup is hard. It requires constant work to follow all the rules.

Pricing:

• Elements (Starter): Starts at $20 per month (very limited features). ‍
• Elements Plus: Starts at $525 per month (where the real tools begin). ‍
• Professional/Enterprise: Custom pricing. This often costs thousands every month.

14. Instantly  

Best For: Sales teams and agencies doing large-scale email marketing campaigns.

Instantly is an all-in-one platform. It is made for cold outreach at scale. Its main strength is its flat-fee warm-up system. This system protects and builds the reputation of many email accounts. It fixes the biggest problem for cold emailers.

Key Features:

• Unlimited Warmup (Flat Fee): You can connect and warm up unlimited email accounts for one price. ‍
• 1M+ Deliverability Network: It uses a huge number of real email accounts. This creates positive signals. ‍
• Slow Ramp Automation: It slowly increases the sending amount. This makes the sending look human. ‍
• SISR (Server & IP Rotation): This high-level feature switches IPs and servers. This keeps reputations safe for heavy senders. ‍
• Unibox & AI: You get one central inbox. AI helps you manage replies and monitor results.

Pros:

• It is the most cost-effective cold email software for agencies.
• Setup is fast and easy. Warm-up is automatic with one click.
• It combines sending and warm-up in one efficient platform.

Cons:

• Reports focus on sales results. They do not offer deep technical checks like other tools.
• Some experts argue about how effective its large, private network is.

Pricing:

• Growth: $37 per month (Unlimited Warmup, 5,000 Emails per month). ‍
• Hypergrowth: $97 per month (Unlimited Warmup, 100,000 Emails per month). ‍
• Light Speed: $358 per month (Includes advanced IP rotation and 500,000 Emails per month).

5 Actionable Steps to Improve Deliverability in 2025

Tools are essential, but they must be paired with the right strategy.

1. Authenticate or Die

You must set up SPF, DKIM, and DMARC. In 2024, Google and Yahoo made this mandatory. Use MxToolbox or Inbox Radar to verify these are active.

2. Warm Up Every New Account

Never launch a campaign on a fresh domain. Use TrulyInbox or Smartlead to slowly ramp up activity for 2-3 weeks before sending real campaigns.

3. Monitor Your "Spam Rate"

Keep your spam complaint rate below 0.1%. If it hits 0.3%, you risk being blocked. Use Google Postmaster Tools to watch this metric like a hawk.

4. Clean Your List

Remove anyone who hasn't opened an email in 6 months. These "zombie" accounts hurt your engagement score. Use ZeroBounce or NeverBounce (honorable mentions for list hygiene) to scrub your data.

5. Test Before You Send

Don't "hope" it lands in the inbox. Run a placement test with Inbox Radar or GlockApps to confirm you are landing in the Primary tab, not Promotions.

The Critical Role of Data Quality in Deliverability

Every great email campaign starts with clean data. You can use the best tools in the world—the fastest warm-up, the deepest placement checker—but they will all fail if you send to bad email addresses.

Sending to a hard bounce (a fake or dead email) is the quickest way to destroy your sender score. This tells providers like Gmail that your list is sloppy, and they will send your next emails straight to spam.

This is why SMARTe protects you. It acts as the first line of defense for your reputation.

SMARTe is a B2B data intelligence platform. It ensures your sales and marketing teams only send emails to verified, active professional contacts from the very beginning.

• It checks every B2B email address to make sure it is real and active.
• It enriches your old data, filling in missing job titles and company details.
• The Chrome Extension lets you find a prospect's verified email and mobile number instantly while you browse LinkedIn.
• It uses Data-as-a-Service to provide the most current contact details, preventing bounces before you even hit send.

By using SMARTe, you stop hard bounces and keep your lists clean. This ensures your expensive deliverability tools actually work on high-quality leads. Great data means great deliverability.

Ready to protect your sender reputation from the ground up?

➡️ Book Your SMARTe Demo Today!