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Best Email Verification and Validation APIs

Best Email Verification and Validation APIs
Written by prodigitalweb

Are you willing to drive traffic to your website, increase customer engagement, or want to enhance the visibility of your brand? If this is the case, you need to choose the best email marketing tool. Businesses are using this strategy for the past few years to varying degrees of success. But, more often than not, email marketing can’t produce the results that we want due to some issues that remain unnoticed in the initial stages. Let’s check the best email verification and validation APIs in this blog post

Email marketing, which is one of the most effective channels, can help you to reach out to the targeted audience who are able to resonate with your services or products. As per reports from Statista, 3.9 billion was the complete number of email users globally in 2019, and in the next year, the number is expected to reach 4.48 billion, almost half of the global population.

Several reasons can be there that can cause the issue, like incorrect email addresses & poor-quality emails. It is essential to verify the emails for accuracy & quality. Hence, Email Verification APIs play a crucial role. An email verification or validation tool lets you know if an email is valid & deliverable.

What is email verification?

Email verification is a process where an email is checked to know if it is accurate, valid, & deliverable. The email verification tool can do this easily. The software follows techniques like syntax check, detection of disposable addresses, domain check, etc.

Remember that these can bring several benefits to entrepreneurs who are willing to produce leads for a bootstrap startup. Besides, companies that want to be completely sure about email lead quality get many benefits from using these tools. There are a few boons of email validation & verification, such as preventing hard bounces and benefitting enterprises to avoid emails being marked as spam. In addition, by using these tools, businesses can avoid wasting money on non-existing email leads.

What is an Email Validation or Email Verification API?

It is a kind of API designed to automatically detect whether email addresses are valid or not. In addition, these tools help the users to get rid of such email addresses that are fake, disposable, or mistyped. These tools help companies to protect their fame by ensuring that they verify email addresses before a message is sent.

This method includes:

  • Checking for invalid formats
  • Catching & correcting misspelt emails
  • Reporting when it was used last and how long it has been active.
  • Confirming that the emails are registered in the domains

If you are a developer with an app that needs new people to register or have an enterprise with a massive mailing list, these tools let you verify and learn how many email addresses are validated. Thus, you will be able to make an informed decision. Every email running through validation API depends on its accuracy, and based on this, these are categorized. Whether API suspects that emails are not authentic, it can isolate this and give you instructions for removing the address or correcting the errors.

Why you need  Email Verification and Validation APIs :

Marketing teams emphasize building the email list. But all emails may not be genuine. If you continue to send emails to the wrong or invalid address, it results in higher bounce rates. Besides, ISPs might treat your email address as Spam. As a result, all emails will go to the user’s spam folders. And no user will ever read it. However, having an email verifier can give you the solution. If you build an email-related product or website, you have to integrate this with the email verifier API you will use. It gives multiple possibilities, including:

Reduced bounce rates:

Email verifiers can display detailed results. They showcase wrong role-based addresses allowing the messages to land on the desired destination. When you have this information in your hand, removing unnecessary addresses to reduce bounce rates will be possible.

Clean email list:

You can use the email API to check email addresses, and in this way, it is possible to remove invalid addresses. In this case, you will get a clean list of only the genuine people with whom you would love to engage.

Choose a Better Email Sourcing Method:

Verification lets you sort through all emails you receive from different sources. As a validation API is able to highlight invalid emails, it is possible to compare how many are coming from every source, like web form, sign-up form, or landing page, etc. Thus, you are capable of analyzing & fine-tuning email collection procedures. It enables you to acquire more valid email addresses than invalid ones.

Helps To Keep Your Email List Updated:

Email addresses used by the leads and subscribers do not remain the same forever. It may happen that an email ID which is valid for now but might not be valid later. Always remember that the email verification procedure keeps the email list updated. Thus, you can ensure that you will always send emails only to email addresses that are authentic & exist already.

Improve email deliverability:

When you remain aware of useful email addresses on the list, you will be able to send emails to only those people. It indicates that the percentage of emails that are getting delivered to the correct inbox will increase. You will be able to compare earlier results with the current results to see improvements in email deliverability.

Cut down cost & saves time:

If you want to store and send emails, you should know that it involves a bit of cost & obviously time. We know it is very difficult to collect the email list, maintain these, & send a personalized email to all. If you want to send emails to genuine people only, you need to filter out all incorrect emails. It saves both time & expenses.

Protects your reputation:

If you send emails to invalid addresses for quite some time, it might lead ISPs & ESPs to consider you as spam. It can even blacklist your domain. Thus, the fame of the sender deteriorates. However, users can prevent mishaps using email verifiers, enabling them to send their messages to the targeted audience without any risk of recipients flagging email addresses as spam. Above all, email verifiers can secure the sender’s reputation.

How do you integrate an email validation API?

If you are willing to identify & catch incorrect email addresses, it is essential to integrate validation APIs with your website or app. Let’s see how you can find & integrate email validation/verification API:

Register for a Free Account:

If you are not already a user of the email verification API, you need to create an account first. Hence, you need to head toward the website of the tool. Then, you should tap the sign-up button.

Choose an Email Validation/verification API of Your Choice:

As soon as you sign up, you should locate the type you are willing to use. As you will need the email validation API, you need to type it in the search bar. If you are unable to find the API which you want, you should conduct advanced search & filtering. After finding an API which meets your needs, you have to head toward the next step.

Choose a Pricing Plan:

If you want to use your API, your job is to subscribe to a payment plan which is suitable for your requirements. Most of the APIs come with a basic free plan. However, ensure that you check every plan’s terms & conditions before picking one.

Test the API:

After selecting a price plan, you have to go back to the Endpoints tab. Then, you need to test the API. You can do this by changing the input for the endpoint. Thus, you need to hit the “Test Endpoint” button to make a request. Whether you get a response to your request, ensure that API is up to the task.

Integrate the Email Validation  or Verification API into Your APP:

When you find out that your API is functional, you need to integrate this into your app. Then, your job is to head toward the Request Snippet tab and choose the programming language. Now, you need to copy the code snippet into your application.

How Does Email Verification Work?

Every email address is analyzed systematically with the help of different factors to verify this.

Let’s learn how the email verification procedure works.

  1. Syntax Check:

Every email address follows a specific syntax standardized by the IETF, standing for Internet Engineering Task Force and RFC (Request for Comments). Email verifiers are capable of identifying email addresses that do not correspond with the standards. Besides, the verifiers remove these from the mailing list.

It generally checks:

The email prefix refers to the sequence of letters, numbers, & symbols before the “@” sign.

Email domain, i.e., email service provider’s name, which is available after the “@” sign. For instance,

An instance of a wrong email address syntax is xyz#[email protected].

  1. Address Name Detection:

Hence, it is necessary to detect & flag email names that are suspicious or role-based because they affect deliverability because of blacklisting. Instances of a few of those email names are info@, admin@, [email protected], etc.

  1. DEA Detection:

DEA or disposable email addresses are identified & removed by DEA detection. Generally, people for subscriptions & sign-ups, use these temporarily to avoid spam emails.

  1. Spam Trap Detection:

Spam traps can be disguised as email addresses. When you send email marketing campaigns to such addresses, these will get a spam mark. It affects the sender’s fame. If you want to prevent it from happening, use email verifiers which can remove spam traps from the email list.

  1. DNSBL & URI DNSBL Check:

When you use an email checker, you can find this running your email via a DNSBL (DNS-based black hole list) and URI (Uniform Resource Identifier). You should know that the DNS-based black hole list contains IP addresses used in spamming, whereas the other one contains domain names in spam email bodies.

  1. MX Record Lookup:

It is possible to check an email address’s MX records to identify invalid domains and verify them. MX records refer to the resource records within the DNS. This system helps to clarify which mail server will accept emails from a domain and which don’t. Once the verifier is able to detect an invalid domain, it will remove that specific email address from the email list.

  1. Active Mailbox Check:

With the help of an email verifier, it is possible to send a ping request to the server of an email address to verify if it is active. As soon as the request is received & responded to, it will recognize the mailbox as active and authentic.

Best email verification and validation APIs:

We have mentioned the top five best email verification and validation APIs. Let’s check it.

1) NeverBounce:

If you have businesses, startups, and non-profit organizations and want to check as well as confirm the email addresses, this tool will be an excellent option. You can use the tool to find & remove duplicate emails, detect threats, validate email lists, etc. In order to check email servers, the platform will use unique methods & Simple Mail Transfer Protocol or SMTP capabilities.

Using this tool, businesses are able to verify emails on lead generation pages, registration forms, etc., where people put their email addresses. It is able to sync email data across various systems. The tool is compatible with Zapier, which enables you to easily integrate with apps such as Mailchimp and HubSpot.

Administrators use the tool for detecting different email problems like incorrect addresses, bad syntax, & various kinds of domains, including top-level, subdomains, and fully qualified domain names. The tool can offer a custom API using which businesses can connect the system with other third-party systems. Hence, it is necessary to know that the cost of this tool relies on the number of verified emails and it can provide support via mobile, email, live chat, & other online channels.


Hybrid Verification: Compared to other services, the tool can find more accept-all addresses by combining real-time verification with accept-all detection.

Mail Server Validation: The tool follows advanced mail server verification to recognize people. For instance, it uses SMTP & other unique processes.

Free Scrubbing: The tool removes incorrect emails before the cleaning procedure, and then it addresses bad syntax for free.

Domain Health Check: It allows you to check whether domains are currently live or not. Remember that DNS & MX Validation Email servers are checked for consistency & availability.

High-Risk Detection: Potentially risky emails can be detected & eliminated by the real-time process.

B2B, B2C, International Email support:  Emails can be validated, whether it is a small business or large business, from Gmail, Yahoo, & other major email providers.

Integration: It can easily integrate with renowned 3rd party email platforms such as Campaign Monitor, Drip, HubSpot, Instapage, MailChimp, Marketo, and SendGrid.

Pricing at NeverBounce:

The tool provides pay-as-you-go & monthly billing options. It is essential to give the number of emails required to process & sign up for a free account for receiving the quote if you are willing to pay monthly.

The beginning cost of Pay-as-you-go rates is $0.003 each for up to 1 million emails. This amount can increase by $0.008 for each email for up to 10,000. Users are able to contact the sales team for custom enterprise pricing when they have over one million emails to process.

2) Hunter:

The tool is used to verify if an email address is valid. This tool can showcase the deliverability of an email address with validations & a confidence score. It displays many validation levels, including the format, mail server response, & domain information. The tool is able to show a comparison with its special base of more than a hundred million professional emails. Using the verifier, it is possible to check emails in bulk that means you will be able to verify the entire email list. It can connect with an SMTP server directly in the procedure, without sending any email to the users. It performs various verifications like checking the format, gibberish, disposable and webmail emails, MX records, accept-all domain, SMTP check, etc.

Users can select the free plan that comes with 50 requests. However, you can choose paid plans starting at $49 every month for 1000 requests. The pain plans include complete results with exports for domain search, many Gmail connections, & priority support.


Bulk email list verification: It enables you to upload a complete list for verification purposes.

Single email verification: Users can use this on Hunter’s Email Verifier page to verify email individually.

API verifications: With the help of the tool’s API, you can integrate with the tools which you use for collecting emails.

Pricing at Hunter:

Hence, the pricing structure depends on requests. Every email verification counts as a request, as does a single domain search & single email finder inquiry. Its plan starts at €49 monthly for 1,000 requests. You can use a free plan allowing 50 requests every month.

3) Quick Email Verification:

Along with small businesses, Fortune 500 companies use this one of the best email verification and validation APIs. The high-precision email validation confirms 99% deliverability. Each email is put through many tests like domain validation, MX record checking, and deep-level SMTP verification. Therefore, while these can identify invalid or undeliverable emails, these help to spot disposable emails. The unique thing is that the verification system stands out due to the high data security standards. Data will always remain encrypted with the latest enterprise-grade encryption. In addition, this company is considered one of the earliest GDPR-compliant email verification companies.


Free trial: In the whole industry, they have probably the most generous free trial. Users can get 100 free email verification credits daily. So, the number of free credits monthly becomes 3000.

Data security: Its servers’ location is US. This tool uses industry-leading security measures to secure user data. It is also possible to check their Privacy Policy online.

Always on: The way they’re working is based on a zero downtown rate policy. Therefore, no matter your time or volume — their service always remains on.

Flexibility: Several file formats are available to use when you upload & download. You can get customized service — no matter how large or unique your needs are.


The starting price of this smallest plan is $4 for 500 credits. With the growth of your volumes, it is possible to enjoy excellent volume discounts.

4) Zerobounce:

It is especially for email marketers because they need to reduce bounce rates so that their business maximizes ROI. Users can enjoy a 360-degree view of emails using this API, covering over thirty status & sub-status codes.

Using a comprehensive dashboard, it is possible to monitor the overall health related to email verification. You can see here regular or monthly reports. If you want, you can even choose the time range to view them. The dashboard shows four various detailed reports concerning individual status codes. The API has interactive graphs with points on what is possible to hover for getting information. Users can even tap on a sub-status or status displayed in the legend to filter the chart & see desired data.

While it informs users if any email address is valid, it can do IP address geolocation. It enables you to test email addresses on the mail server before emails are sent. It is possible to integrate the API with your website or app easily. While it needs a few lines of code, it lets users enjoy the quick API. Using API Sandbox is also possible whether you want to test your code implementations to validate email.

With the help of this API, you are able to identify spam traps, abusive addresses, etc & remove them. Also, it helps to detect the misspelt domains from the list of emails you have. In addition, it is possible to control spam complaints & secure IP reputation. AI has been leveraged to produce a scoring system that is able to create quality scores of email addresses.

It can integrate with different SDKs, including .NET, Python, PHP, Swift, Java, etc. Moreover, this API can integrate with Gmail, Drip, GetResponse, Facebook, Excel, Mailchimp, Salesforce, Shopify, Slack, Magento, and other platforms.

It uses geo-redundant servers for availability. This API can leverage anti-greylisting technology to deliver accurate results. In addition, it enables you to detect the gender of some emails by viewing the first names.


Bulk email list verification: You can upload the whole list for processing.

Single email verification: It helps to verify emails to check if any of them is invalid.

Real-time verification API: By integrating its verification API with the forms of your website, it is possible to stop incorrect emails from being added to the email list.

Key customer data: This API appends key data to those addresses which are valid. The data includes several things such as the subscriber’s name, gender, geolocation, etc.

Integrations: This one can integrate with famous email providers & services.

Pricing at ZeroBounce:

It offers credits & subscription plans. Hence, its credit system is a pay-as-you-go option. The starting price is $16 for 2,000 email verifications. On the other hand, the premium plan begins at $15 monthly with a 6% discount for 2,000 email verifications.

5) MailerCheck:

This one is an excellent email validation platform from the company behind MailerLite, a renowned email marketing platform. It has the best email delivery rates in the industry. Besides, the number of customers of this platform is 1.1 million. It can check inactive mailboxes, typos, disposable email boxes, syntax errors, etc.


Bulk email verification: It uploads a CSV or connects this with your email provider for verifying email addresses in bulk.

API integrations with renowned email providers: If you are willing to pull the whole email list from GetResponse or ConvertKit, this API is a great option.

Individual email verification: It lets you verify individual email addresses.

Reporting: You can receive a detailed report when you verify bulk emails or use API integrations.

Pricing at MailerCheck:

You can select one-off credits starting from $10 for 1K email credits. The cost required for every email verification drops if you buy more credits. Alternatively, saving 20% is possible with a monthly subscription.


Best Email Verification and Validation APIs can detect automatically whether email addresses are valid or not and help the users to get rid of those email addresses which are fake, disposable, or mistyped. These tools help the users to maintain a clean email list along with boosting their email deliverability. Just choose any of the above-mentioned best email verification and validation APIs and bid goodbye to spam traps, fake email IDs & inactive mailboxes.

Frequently Asked Questions

  •  What is real-time email validation?

This one is an advanced feature that you can find in many email verification tools. The feature lets the tool verify email addresses because these are entered in the sign-up form. Users will immediately be made aware of the incorrect email addresses & typos, rectified in real-time.

  • How can you verify your emails in bulk?

In most cases, established businesses have long email lists. If you don’t use an email validation tool, verifying email addresses will take a lot of time.

Fortunately, these tools help to verify emails in bulk, and users do not need to make any effort.

  • What is an email validation tool?

It is a kind of tool that can employ a verification process wherein the deliverability & validity of every email address are verified for errors & inaccuracies. These help to detect typos, spelling errors, etc. Therefore, you can get a chance to improve the quality of your email before sending them. When you use these tools, you will get to know if the email address to which you want to send an email exists or not.

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