How can I use an API to suppress or reject fake emails on my signup form?

Summary

Implementing an email validation API on signup forms is a proactive strategy to prevent fake or disposable email addresses from entering your system. These APIs offer real-time verification, including syntax checks, domain validation, mailbox existence verification, and assessments for disposable email addresses, spam traps, and other risky indicators. Services like Kickbox provide address quality scores and typo corrections. CAPTCHAs and rate limiting can be used in conjunction with APIs to mitigate bot signups. Overall, these measures help maintain a clean email list, enhance data quality, and improve email marketing performance. Ethical considerations are important, emphasizing the need to avoid discrimination when using these tools.

Key findings

  • Proactive Prevention: Email verification APIs prevent fake and disposable emails from entering your system.
  • Real-time Validation: APIs provide real-time validation, including syntax, domain, and mailbox verification.
  • Bot Mitigation: CAPTCHA and rate limiting help mitigate bot signups.
  • Enhanced Security: Reduces risky emails and improves signup security.
  • Data Accuracy: Enhances the accuracy and integrity of your email list.
  • Performance Improvement: Boosts email marketing performance by reducing bounce rates.
  • Risk Reduction: Helps to reject disposable emails, spam traps, and other problematic addresses.

Key considerations

  • Integration Complexity: API integration requires technical expertise and careful implementation.
  • Cost: API services involve costs that need to be considered.
  • Ethical Usage: It is important to avoid discrimination and use these tools ethically.
  • Service Comparison: Service comparison is important to select the appropriate API and features.

What email marketers say
8Marketer opinions

Implementing an email validation API on your signup form is a proactive approach to prevent fake or disposable email addresses from entering your system. These APIs work by performing real-time checks on email addresses, including syntax, domain validation, mailbox verification, and comparisons against databases of known fake addresses. In addition to an email validation API, a CAPTCHA can be used to prevent bots from signing up and limit the number of API requests to secure endpoints. These methods work together to help ensure that only valid and active email addresses are added to your list, reducing bounce rates, improving overall email marketing performance, and enhancing the integrity of the email list.

Key opinions

  • Proactive Prevention: Email verification APIs prevent fake or disposable emails from entering your system.
  • Real-time Checks: APIs perform real-time validation, including syntax, domain, and mailbox verification.
  • Improved Data Quality: Validation enhances the integrity of the email list by reducing invalid addresses.
  • Performance Boost: Reduced bounce rates and improved email marketing performance are achieved.
  • Bot Mitigation: Combine with CAPTCHA to avoid bot signups, enhancing security.
  • Mistake Correction: Validation can help to catch common mistakes such as typos and temporary accounts.

Key considerations

  • API Integration: Carefully integrate the API into your signup form to ensure a seamless user experience.
  • Balance: Use rate limiting to avoid abuse but balance this with legitimate user volume.
  • Multiple Methods: Use multiple methods to prevent fake or disposable emails.
Marketer view

Email marketer from Webmaster Forum says that email validation APIs can reduce the number of invalid addresses, improving the integrity of the email list and overall marketing efficiency.

January 2022 - Webmaster Forum
Marketer view

Email marketer from Email Geeks shares that you can add a validation API to your signup form to stop invalid emails from entering your database, catching a large portion of them.

November 2021 - Email Geeks
Marketer view

Email marketer from ZeroBounce explains that integrating an email validation API helps ensure that only valid and active email addresses are added to your list, reducing bounce rates and improving overall email marketing performance.

November 2023 - ZeroBounce
Marketer view

Email marketer from Hunter.io shares that implementing an email verification API on your signup form is a proactive way to prevent fake or disposable email addresses from entering your system, improving data quality.

October 2021 - Hunter.io
Marketer view

Email marketer from Reddit shares to use an email validation service with an API to filter fake signups. Recommends checking for common typo domains and disposable email addresses.

February 2024 - Reddit
Marketer view

Email marketer from Clearout shares that email validation API can improve accuracy by combining syntax checks, domain validation, and mailbox verification. They also check against a database of known fake addresses.

June 2021 - Clearout
Marketer view

Email marketer from StackOverflow shares that adding a CAPTCHA in addition to email verification API helps avoid bots from signing up. Suggests rate limiting API requests.

April 2021 - StackOverflow
Marketer view

Email marketer from EmailListVerify explains their Javascript API can be integrated into signup forms to validate email addresses real-time. This service catches common mistakes such as typos and temporary accounts.

December 2023 - EmailListVerify

What the experts say
5Expert opinions

Email validation APIs can be used to enhance signup form security and data quality by mitigating bot signups, detecting typos, and identifying disposable email addresses. Services like Kickbox offer APIs that provide scores indicating email address quality and suggest corrections. These APIs can also flag and reject spam traps, complainers, litigators, and disposable email addresses, ultimately helping to maintain a clean and engaged email list. It's important to ensure you use email validation APIs ethically and avoid discrimination.

Key opinions

  • Bot Mitigation: Nocaptcha helps mitigate bot signups.
  • Typo Detection: Services like Kickbox can detect typos and suggest corrections.
  • Quality Scoring: Kickbox API provides scores (Sendex) to indicate email address quality.
  • Address Flagging: Validation services flag disposable and single-use email addresses.
  • Broad Rejection: Validation APIs can reject spam traps, complainers, and litigators.
  • Ethical Usage: Ensure ethical use and avoid discrimination when using validation APIs.

Key considerations

  • Integration Complexity: Integrating validation APIs effectively requires technical expertise.
  • Ethical Implications: Carefully consider ethical implications when using validation APIs.
  • Cost Factors: Factor in the cost of using validation APIs.
Expert view

Expert from Email Geeks explains that Kickbox has an API that provides a thumbs up/down rating and a Sendex score to indicate address quality, along with possible corrections for mistyped domains.

April 2021 - Email Geeks
Expert view

Expert from Word to the Wise explains that Validation APIs can be used to also reject spam traps, complainers, litigators, and disposable emails.

November 2024 - Word to the Wise
Expert view

Expert from Word to the Wise explains that Email validation APIs should be used to help suppress and reject fake emails to prevent invalid emails making it into your list, but also to ensure it's used ethically and not to discriminate.

March 2024 - Word to the Wise
Expert view

Expert from Email Geeks explains you can add nocaptcha to mitigate bot signups, and Kickbox can detect typos and suggest corrections.

February 2022 - Email Geeks
Expert view

Expert from Email Geeks explains that validation services will also flag whether they think it’s a single use or disposable email address.

March 2024 - Email Geeks

What the documentation says
6Technical articles

Email validation APIs from providers like Mailgun, Kickbox, AbstractAPI, Email Hippo, Debounce.io, and NeverBounce can be integrated into signup forms to identify and reject invalid email addresses in real-time. These APIs verify email syntax, domain status, mailbox existence, and check for disposable emails, typos, and other indicators of fake accounts. This process helps filter out risky or invalid signups, enhances signup security, and improves overall data accuracy.

Key findings

  • Real-Time Verification: APIs offer real-time verification of email addresses.
  • Multi-Faceted Checks: Checks include syntax, domain, mailbox, and disposable email status.
  • Fake Account Detection: APIs help detect and reject fake accounts.
  • Signup Security: These APIs improve signup security by filtering out risky emails.
  • Data Accuracy: Data accuracy is improved by removing invalid addresses.

Key considerations

  • API Integration: Careful integration into signup forms is crucial for a seamless user experience.
  • Cost: Consider the cost implications of using these APIs.
  • Feature Comparison: Compare features of different APIs to find the best fit.
Technical article

Documentation from AbstractAPI explains that using their Email Validation API you can check the format, domain, and mailbox existence of an email address, helping to filter out invalid or fake emails during signup.

December 2024 - AbstractAPI
Technical article

Documentation from Debounce.io shares their email verification API provides an all-in-one solution for filtering risky emails by checking email syntax, domain reputation, and disposable email status in real time, to enhance signup security.

February 2023 - Debounce.io
Technical article

Documentation from Mailgun explains that their Email Validation API can be integrated into signup forms to identify and reject invalid email addresses. It detects typos, disposable emails, and other indicators of fake accounts.

April 2024 - Mailgun
Technical article

Documentation from NeverBounce explains their comprehensive email cleaning service validates in real time, filtering fake emails. Offers features like syntax verification, domain checks, and risk assessment to boost signup accuracy.

August 2024 - NeverBounce
Technical article

Documentation from Kickbox shares that their real-time email verification API allows you to verify email addresses as they are entered on your signup form, preventing fake or invalid addresses from being added to your list.

March 2022 - Kickbox
Technical article

Documentation from Email Hippo shares that with their API, developers can filter out invalid signups by checking the email's syntax, domain status, and whether the email is a disposable address.

March 2025 - Email Hippo