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March 10, 2024

The Best Email Verification APIs in 2024

Joey Maddox
Head of Growth
The all-in-one platform for stopping Fake accounts

Temporary email domains. Duplicate email addresses. Bot generated accounts. These common and unsophisticated cyber attacks can ruin your email deliverability, allow users to get around paywalls, and ultimately prevent your company from understanding its customers base.

It’s a simple problem - luckily, there are lightweight, inexpensive solutions. Today, we discuss the four best software solutions for verifying email addresses. By the end of this article, you’ll have a better understanding of 1) what are fake email addresses, 2) why they're an issue, and 3) how you can combat it!

The four best temporary email detection softwares

  • ZeroBounce: Robust solution built with email deliverability in mind; priciest of the bunch
  • Verisoul’s Email CheckPoint: Low-cost solution that excels at checking linked accounts and disposable domains
  • VerifyMail: Singular focus on checking for disposable domains, lacking in other features
  • MailCheck: Leverages social networks to help make sure emails are real; questionable reputation

What is a fake email address?

Wow, look at you - you aren’t skipping to the the sparknotes on the different solutions. For that, we say THANK YOU. You can’t stop a problem you don’t know you have… and you don’t know what you don’t know.

Fake emails come in all shapes and sizes. The only thing scarier than a fake email address is the false sense of confidence most software companies have. The three most common types of fake emails:

  • Temporary emails: These are auto-generated emails that use temporary or disposable domains. A quick google search of “temporary mail” yields dozens of platforms like TempMail. These temporary email generators not only create disposable domains (domains that will go out of service in a few weeks), they also provide an inbox that allows you to bypass basic email verification checks.
  • Duplicate emails / aliases: An alias email address (where two emails “point” to the same address) or multiple email addresses made by the same user. These use periods and + signs to create unique aliases for the same email. For example:
    a)  + Alias:, - these are the same email
    b) . Alias: is still the same email as the two above
  • Bot generated accounts: At the most extreme end of multi-accounting, you might have bots creating as many accounts as possible on your platform. If you’ve ever left an input form out on your website, odds are you’ve seen absolute JUNK come through from bots.
Using a temp email to sign up for a temp email check provider - the irony!

Who is making these, and why does this matter?

So who’s creating these fake emails? While it’s nice to think that the average person wouldn’t create fake emails, even honest people may use them to save time, save money, reduce marketing content in their inboxes, or remain private. Dishonest people love them for, well, dishonest reasons.

What’s the end impact on you and your business?

  1. Fake Accounts: Users spam your promotional and referral programs
  2. Lost revenue: Potential customers don’t convert, as they continue to leverage free trials and get around paywalls
  3. Worsened lead/customer engagement: Your ability to connect with potential prospects or existing customers is hampered, as emails either don’t deliver or are never opened
  4. Inappropriate access: Users outside of authorized jurisdictions gain access to your content
  5. Cyber-risk: Bad actors rejoin platforms after being kicked off and continue to remain a threat

How do I combat these fake accounts?

There are generally two approaches: public lists or email authentication softwares.

Public Lists

Public lists are free and require no third-party engagement. Your dev team simply checks a public list of blocked domains. It’s a fairly passive approach for an active problem: these fake email generators are always one step ahead of the public lists. By the time the list gets updated with the fake account domains, the generators have switched to a new domain. A few examples of free, easy-to-use lists on Github:

Our recommended approach is email detection APIs. These providers actively maintain a list of blocked domains by checking social media profiles, manually reviewing new domains, visiting all new domain sites in an automated fashion, and/or scraping all available public lists daily.

Disposable Email Detection API

Without further ado, our four softwares:

1. ZeroBounce
ZeroBounce Dashboard


  • Strong solution for email marketing (i.e., making sure emails are real and won’t bounce)
  • One of the best at checking for validity of emails
  • Reputable software with enterprise customers including Netflix and Disney
  • Integrations with other email marketing tools


  • Expensive (~$0.01 per API call)
  • Limited functionality outside of deliverability
  • Does not detect duplicate or similar emails
  • Slow API takes 3 seconds
  • No dashboard / analytics

Free option: 100 free email validations upon sign-up


ZeroBounce is a great option for marketing teams - it will help ensure your marketing emails reach their desired inboxes. However, it’s expensive, and only the right solution to one of many impacts to your business per our above list. If you’re in need of cybersecurity software, it likely isn’t suitable.

2. Verisoul’s Email Checkpoint
Email Checkpoint Dashboard


  • Completely free, enterprise grade API
  • Checks email similarity / duplicate emails with AI
  • Strong domain checking database which is actively updated
  • Tests for business vs personal emails


  • Checks deliverability only at the domain level
  • Includes private API key, but doesn’t include pre-built integrations with other marketing or cybersecurity tools

Free option: 100% free plan with rate limit


Verisoul’s Email Checkpoint is the lightest, cheapest, and most accurate solution for IT professionals when it comes to checking email domains. It’s backed by reputable VC funds and has a strong founding team, but is smaller than ZeroBounce. The full Verisoul platform offers much more functionality than Email Checkpoint, is also more expensive.

3. VerifyMail
VerifyMail Dashboard


  • Multiple plan options
  • Human checking team verifies whether sites are disposable
  • Offers multiple plan options with reasonable prices


  • No email duplicate or similarity detection
  • No dashboard
  • Because they use manual labor, they are often slow to add new disposable domains
  • Unsure who is behind it / reputability - doesn’t seem fit for enterprise or production apps that need reliability

Free option: Only 3 API calls per day, which is essentially unusable


VerifyMail is a lightweight solution. They’ve built a nice list of disposable domains, albeit in a manual fashion. The biggest knock on VerifyMail is their reliability / trust; there’s almost no online presence, and it’s not 100% clear who is behind the company. The dashboard is essentially non-existent, as the screenshot above highlights (only shows API usage over time).

4. MailCheck
MailCheck Dashboard


  • Affordable fixed plan at $50/month
  • Easy wordpress plugin
  • “Proactive” gathering of disposable domains


  • No email duplicate or similarity detection
  • Unsure who is behind it / reputability - doesn’t seem fit for enterprise or production apps that need reliability

Free option: 10 free email checks w/o credit card, 100 free email checks w/ credit card


MailCheck does a nice job of offering an affordable disposable domain checker, and is a quality point solution for domains specifically. The dashboard feels a bit more professional than VerifyMail, though it’s still unclear how reliable this product is. That said, their website does a nice job of answering all FAQs on what the problem is and how they address it.

So which offering should you use?

Like most authors, I’m inclined to say “it depends.” However, unlike other articles, I’m willing to draw a line in the sand.

If you’re searching for email deliverability tools, it’s clear that ZeroBounce is your best option. They offer a broad feature set in addition to simple email verification, and their tests on bounce rates are much more comprehensive than other users.

If you have an IT angle, Verisoul’s Email Checkpoint is who we’d recommend. It’s more robust as the other offerings, has unique features like AI email similarity scoring and detection of work vs. personal emails, and is the cheapest among all four offerings. In addition, you can go beyond basic email verification checks and get into network, device, and user behavior risk when you use the full platform.

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Joey Maddox
Head of Growth
Joey is the head of growth at Verisoul. Prior to joining, he worked on growing B2B Software companies as a Senior Associate at PE group Serent Capital. Joey was also a former consultant at Bain & Company.

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