Phone Verification API for Test Automation Teams
4 min readLearn how a phone verification API supports signup, login, recovery, and MFA test automation with programmable numbers, deterministic waits, and real message assertions.
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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OTP testing and OTP checker workflows for email, SMS, magic links, and MFA
14 min readUse OTP testing and OTP checker workflows to validate email codes, SMS verification, magic links, MFA, expiry, resends, and one-time use.
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NBSP Character Explained: How To Use Non-Breaking Spaces in HTML and Email
6 min readLearn what the NBSP character means, how ` ` works in HTML, when to use non-breaking spaces, how it differs from normal spaces, and how to debug formatting problems in web pages and email templates.
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MX Record Lookup Guide: How to Verify Email Routing and Troubleshoot Delivery
5 min readLearn what MX records do, how to check them with dig and nslookup, how MX interacts with SPF, DKIM, and DMARC, and how to verify email routing safely.
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Mailto Link Guide: Syntax, HTML Examples, Parameters, and Better Alternatives
7 min readLearn how a mailto link works, how to build mailto syntax in HTML and JavaScript, how to encode subject and body fields correctly, and when to use an email API instead.
Read guideInbound Email API: Receive, Process, and Route Messages
9 min readSee how MailSlurp receives inbound email, sends NEW_EMAIL webhooks, retrieves messages and attachments, and routes replies into application workflows.
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IMAP vs POP3: Which Email Retrieval Model Should You Choose?
4 min readCompare IMAP and POP3 for real mailbox workflows, understand where SMTP fits, and choose the right retrieval model for support, client setup, migration, or testing.
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HTML Email Creation and Sending: Templates, CSS Constraints, and Safe Testing
5 min readLearn how to build HTML emails that survive real clients, send them reliably through SMTP or APIs, and validate links, layout, and delivery before release.
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How to Use the Gmail API for Automated Email Testing in CI
5 min readLearn how to use the Gmail API to verify OTP, password reset, and transactional emails in automated tests, and when a dedicated test inbox API is the better choice.
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How to Send Email in Java with SMTP, HTML, and Attachments
4 min readLearn how to send email in Java with SMTP using Jakarta Mail, including plain text messages, HTML email, attachments, TLS setup, and safe inbox-level testing.
Read guideHow to Send Email From Excel: VBA, Outlook, and No-Macro Options
8 min readLearn how to send email from Excel using VBA, Outlook, mailto formulas, and SMTP. Covers bulk email, attachments, HTML email, and safer alternatives.
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How to Build Reliable Email Testing in CI with a Test Inbox API
4 min readLearn how QA and engineering teams can stop flaky signup, reset, OTP, and notification tests by using isolated inboxes, explicit waits, and API-driven assertions.
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