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    Your Guide To Email Deliverability Testing Tools

    Written By Jason Rowse - Digital Marketing Expert

    Updated: 09/06/2021

    Email Deliverability Rate: What It Is And What It Is Not

    Using advanced tools like inbox placement can determine the efficiency of the marketing program. 

    Still,before you invest in an email deliverability tool, it is important to understand the nuances of this software.

    While delivery counts whether a subscriber received your mail or not, the rate is used to determine if your marketing email reached the inbox or spam folder after being screened by the subscriber’s email server. 

    Here are a few reasons why deliverability rates are affected: 

    • Your reputation 
    • Past history with recipient’s server
    • Verification/authentication 
    • Content quality 

    Top 5 Email Deliverability Testing Tools 

    To ensure that your inbox placement tester meets the rigorous demands of your campaigns, you need to hunt for features like multifaceted spam checks, advanced reporting tools, cost-effective pricing, and error management. 

    The following will help you analyze the pricing, and features of five applications so that you can pick the most suitable option.  

    1. Mail-Tester


    • Free for up to three checks per day
    • Premium: €50 for 500 tests at €0.10 per test to €20,000 for 1,000,000 tests at €0.02 per test

    Using a simple scoring model from 0-10, Mail-Tester rates the quality of your electronic-messages. While scoring above nine is ideal, rates below five require critical attention. 

    To generate the efficiency score, Mail-Tester screens the HTML of your emails besides analyzing the content and domain for spam.

    Combined with easy integration with existing email marketing software via API, this email deliverability tester is good for small to large enterprises.  


    • SpamAssassin filter 
    • SPF and DKIM setting 
    • Compare with blacklisted IP addresses
    • Check for broken links
    • Screen for errors in the content 
    • Daily, weekly and monthly stats of results  
    • White label options 

    2. GlockApps 


    • Basic: $39 for 6000 tests per year
    • Business: $79 for 18,000 tests per year
    • Agency: $159 for 60,000 tests per year 

    GlockApps is an email deliverability testing software that helps marketers identify and improve the performance of their marketing emails.

    To do so, this application reproduces your test email via SendGrid, Postfix, and Mailgun. It then calculates the probability of your email landing in the inbox, tabs, spam, or missing delivery altogether. 

    The best thing about GlockApps is its insightful and in-depth report generation for ISPs and corporate parameters.

    Recommended as the best testing platform for detecting email spoofing and attacks, this app also screens messages for spam words and other risks.

    Yet another benefit is the spam score testing with Google Spam Filter, Barracuda, SpamAssassin, and Mimecast, making it ideal for SMEs. 

    Get started with GlockApps while saving funds as it offers the first three tests for free. 


    • Inbox placement analysis 
    • Content analysis 
    • Sender score
    • Tests against 50+ Blacklists 
    • DMARC, SPF and DKIM compliance  
    • Track delivery duration
    • 20 automatic tests  

    3. SendForensics 

    Pricing per month

    • Package A: $49 for two domains 
    • Package B: $79 for five domains
    • Package C: $199 for 15 domains
    • Package D: $349 for 30 domains

    SendForensics compares your email performance with others to determine the probable percentage of emails that will go straight to inboxes as opposed to the spam folder.

    It is best-known for predictive modeling help including word choice suggestions. Essentially, this software analyzes the quality of your marketing messages against global standards to recognize critical risks. 

    Experts recommend their pre-send optimization and post-send measurement to keep a tab on the success rate of your marketing emails.

    The client preview is another perk of this testing tool that helps improve engagement rates.


    • In-depth AI-triggered automatic reporting 
    • Live Inbox Placement tests
    • Advanced security and compliance 
    • ESP Engagement Data Assessment
    • Blacklist and Whitelist monitoring
    • Send to 30+ global service providers 
    • Insightful content analysis 
    • Meticulous infrastructure auditing 
    • SPF, DKIM and DMARC authentication  

    4. Mailtrap                 

    Monthly Pricing

    • Free: $0 with up to 500 tests per month
    • Individual: $9.99 with up to 5,000 tests pm
    • Team: $24.99 with up to 15,000 tests pm
    • Business: $49.99 with up to 50,000 tests pm
    • Premium: $99.99 with up to 100,000 tests pm
    • Enterprise: $299.99 with up to 10 million tests pm

    Used by popular businesses like Adobe and GitHub, Mailtrap is a fake SMTP server that admins can use for developmental purposes.

    It works by capturing your outgoing emails to score you from zero to five so that you can amend the campaign details based on risks and alerts.

    The best thing about Mailtrap is that it lets QAs and developers share inboxes directly with their teams to collaborate on campaigns.


    • SpamAssassin tests
    • Collaborate with teams 
    • SPF, DKIM, and DMARC
    • Add and segment inboxes by project
    • Blacklist testing
    • HTTPS and TLS security 
    • Testing via API 

    5. Spamcheck by Postmark 


    • $10 to $1,200 for 10,000 to 5,000,000 emails 

    A unique email testing tool from Postmark, Spamcheck is the best in the industry for examining and screening for spam in emails.

    This tool determines the SpamAssassin score above or below zero. The trick is to get as low a score as possible with five indicating spam messages and 0.1 showing genuineness of your emails. 

    Spamcheck is a great fit for agencies, freelancers, developers, and big-to-small enterprises. It helps evaluate the HTML quality of messages besides offering automated spam analysis on outgoing electronic messages with a free API.


    • SpamAssassin tool
    • Link quality assessment 
    • IP reputation
    • Text to image proportions 
    • Authentication
    • Google Postmaster tools
    • Delivery errors 
    • Credibility levels

    Bottom Line 

    Email deliverability helps marketers determine the true value of their efforts. If you’re new to email marketing, get started on GlockApps or Mail-Tester to use their features for free.

    However, Spamcheck excels in automated spam analysis. When your campaigns need high-performance and the budget is higher, SendForensics is the way to go. 

    In short, every tool has its pros and cons. Begin by signing up for a free trial with the chosen software to gain first-hand experience risk free.