Email Honeypots Explained: How Spam Traps Damage Deliverability
3 min readLearn what email honeypots (spam traps) are, how senders hit them, and how to protect domain reputation with list hygiene and consent controls.
Read guideEmail testing, deliverability, and API guides
Build more reliable email and SMS workflows with practical MailSlurp tutorials, implementation guides, and production-ready testing advice.
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Using animated email signatures can make emails more engaging and visually appealing.
4 min readAdd an animated edge to email communication with GIF signatures. Learn how to make messages stand out with eye-catching animations.
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Typo in Mass Email Marketing: What to Do After You've Already Hit Send
9 min readOops! Correcting Mistakes in Your Marketing Emails: Tips on fixing typos and errors in your mass email without hurting your brand's reputation.
Read guideSMS Testing: Check OTPs, Resends and Login Before Release
8 min readTest SMS receipt and the login it enables. Cover fresh codes, leading zeros, resends, expiry and parallel accounts with a runnable OTP example.
Read guideHow to Embed Images in HTML Email
5 min readLearn how to embed images in HTML email with CID attachments, hosted URLs, or Base64, then test rendering across Gmail, Outlook, and mobile clients.
Read guideEmail tracking software: what to measure and how to choose
6 min readCompare email tracking software by open, click, reply, delivery, and testing signals. Learn what the data means and how to test a tool before rollout.
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Email technology showdown: Postfix vs Sendmail vs Exim
5 min readComparing and Contrasting Email Transfer Tech: Postfix vs Sendmail vs Exim. Learn about different types of MTAs and how these mail transfer agents compare.
Read guideGmail Promotions or Spam? Check Where Your Campaign Landed
7 min readLearn the difference between Gmail Promotions and spam, test a real Mailchimp or Klaviyo campaign, and choose the right next step from the result.
Read guideHow to stop email spam bots on forms and signups
9 min readStop form and signup spam with server-side validation, rate limits, risk-based challenges, email confirmation, and tests that protect real users.
Read guideTesting TOTP one time passwords is a secure way to authenticate users.
3 min readThe Ultimate Guide to Multi-Factor Authentication with OTP Email Traps: End-to-End Testing for Maximum Security
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The Working Principles of 2FA Hardware (two factor authentication)
5 min readUFA and 2FA provide secure authentication for single-sign on applications and is an essential part of modern development.
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Which Industries Require 2FA for Enhanced Security?
4 min readTwo-factor authentication is common security requirement for many businesses. Adding MFA or 2FA user access to your organization or product is essential.
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