MailSlurp technical blog from the developers. Posts about email API testing and features added to the platform and new examples.


What Is Amazon Simple Storage Service (SES) - And How Can I Use It?

Amazon SES is an email service among virtual servers, AI apps, and libraries. Ideally, you can integrate your email system with your program hosted on Amazon.

The Do's And Don'ts Of Mass Email Sending

Replace email blasts with safe transactional mail campaigns - preserve your spam core and deliverability.

Send emails in Swift 5 (on iOS, Mac, and Linux)

Send emails in Swift 5 (on iOS, Mac, and Linux)

SPF Records Explained: What Are They?

An SPF record is now required for reliable email delivery. It protects your emails from being faked. This protects you against phishing scams and trollers.

Maximum Email Size and How to Optimize It

Email sizes are fundamental for a few important reasons. One is security, and another is the performance of your email.

List of free Mailinator alternative

Free disposable email accounts for testing and development!

How to test an email address

Test email accounts for testing email addresses in code or online. Create fake email accounts for testing.

How to mask an email address

Email masking is more critical than ever before. Hide the data behind your address for privacy.

How to choose the right email design size (for various campaigns)

Email sizes can be instrumental to determine if your consumer will comprehend and engage with your content. While the template width (600 px) is typical, there are nuances to be mindful of. There are no hard and fast standards for email template height like design blocks.

HTML Mailto Links Explained

HTML Mailto is uncomplicated to use. This link opens the default email client and adds a new notification maker. Pre-populated fields save time and prevent email bounces. This post will cover customizing mailto. We'll also discuss its viability in this decade. Come on.

Create custom print classes with Tailwind

Configure tailwind.config.js to create prefixed classes with a custom media query.

Confirmation emails that work

Confirmation emails enjoy a 70% open rate; sending nominal "order confirmed" messages is inexcusable. We will teach you how to confirm an email in the article below.

Bounce email: verify address lists to reduce spam

Check email addresses exist before sending emails to reduce bounce-back returns and avoid spam bans.

&nbsp and HTML space tips and solutions

&nbsp, AKA non-breaking space, is a character used in HTML to create a white space. In this post we analyze usage and performance solutions.


Picking the right port for SMTP mailservers

What's an SMTP port and How to Choose the Right One?

Email blast campaigns and how to maintain a good sender reputation.

How do SMTP servers work and what is a fake smtp server

Text messages are split into SMS segments when sent.

What is an Email Newsletter, and How to Create One?

Why sending emails via API services is simpler than deploying your own SMTP server

Emails are sent and transfered between mail-servers using mail server transfer agents.

What is Single Sign-On, and How Does it Work?

Comprehensive SMTP guide for sending and receiving email with the simple mail transfer protocol.

What is SMS Authentication and is it Secure?

What is SAML and How Does it Work?

What is Multi-Factor Authentication (MFA)?

What is Multi-Factor Authentication (MFA), and How Does it Work?

What is MMS Messaging? And how is it Different from SMS?

How to setup and configure DKIM signatures with the sender policy framework (SPF)

How to parse and validate markdown with YAML headers and assert for required meta data lengths.

Generate real email addresses in tests

CAN-SPAM email regulations and the List-Unsubscribe SMTP header

Generate dynamic email addresses on demand with MailSlurp - a modern email API.

User Authentication: Getting the Most Out of SMS OTP

use SMTP queue systems to enqueue email actions for later dates.

Sending emails is important for many applications. Top 10 transactional email services compared.

Test the spam ranking and domain authority of your site or mailserver with these free tools.

Top Testing Frameworks for Android UI

Top 3 email testing tools

Tips for writing excellent email subject lines

The ultimate guide to email testing tools

The ideal email design dimension for various campaigns

The complete guide to Email Marketing

How to test transactional email campaigns and email verification using the best free and paid tools.

UFA and 2FA provide secure authentication for single-sign on applications and is an essential part of modern development.

The Way to Ship a Text via Email (And an email through text): A Simple Guide

The Top 29 Email Automation Software Programs to Grow Your Business

The Recommended Email size

The Most Advanced Guide on Azure Email Sending.

The Difference between POP3 Vs. IMAP Emails

The Best Email Deliverability Testing Tools

Test your email delivery using MailSlurp to ensure high email marketing success.

Text Enabled Toll-Free Numbers: What all Businesses Should Know about Toll-Free SMS

Testing user sign-up with real email addresses in Ruby

Comparison of popular email testing tools versus MailSlurp

Testing Content Security Policy CSP Headers

How to use test email accounts with Jest and NodeJS

Use MailSlurp to create email addresses to send and receive emails during tests.

How to use Telnet to test the SMTP servers?

Fast, strongly typed end-to-end testing

Ten best email fonts that always work well

Stripe get all customers list (example)

Avoid embarrassing bug reports by catching bugs in production early with Smoke Tests. It's a simple way to deploy with confidence.

Show latest package version NPM

Mailinator is a free disposable email testing tool.

Sending emails in NodeJS with Sengrid, SES, or custom SMTP servers.

How to send email attachments using MailSlurp API.

SMTP Port Guide

Check email deliverability using DKIM SMTP

A full list of commands and response status codes for SMTP mail servers when sending emails.

SMS txt shortcodes explaines

SMS Intercept Attacks and Why SMS Multi-Factor Still Matters

Reformat .NET core projects using Resharper CLI tools

Generate email accounts for testing

Use MailSlurp email APIs to fetch and process emails in tests or apps.

Starting sending and receiving emails in no time with MailSlurp's official NodeJS Client.

PHPMailer tutorial (Sending email with PHP)

OTP SMS verification tutorial

Send and receive email using NodeMailer in Node JS.

Pros and cons of creating more than one SPF send policy framework record

Multi-factor Authentication Guide

Multi-factor Authentication (MFA): All You Need to Know

How to specify headers h1, h2, h3 and more in Github flavoured Markdown

Manage Email Throttling Correctly!

Tutorial mailto links in HTML emails

Using MailJet to send emails (and how to test it).

Learn the Right Way to Calculate Email Open Rate

Keeping your email marketing list clean - avoiding bounces and complaints

How to create email workflows with MailCatcher and what alternatives exist?

Use SMS/TXT messaging platforms to send and receive text at scale

Install Swift on Debian (Buster)

Serve responsive picture tags with custom render-image layout partial in Hugo static site generator.

Example tutorial for how to wait until webdriver and Selenium have started during Codeception PHP tests

Mailto links not working guide.

Check new notifications queued in PHP using Laravel's email and SMS notification system.

Use Cypress JS to test emails are received and validated during end-to-end testing.

Many applications use OTP one time passwords to secure their data. See how to test OTP using real email addresses.

Spawn Selenium server process before tests start for easier acceptance testing.

Lately when needing to provide Webp background image image-sets I discovered a way to set the same React inline style property twice.

JS SMTP email sending guide using HTML and NodeJS.

RLang tutorial for sending emails over SMTP.

How to send confirmation emails

Use Send-MailMessage in Windows Powershell to send emails using an SMTP server or MailSlurp's free email API.

You can set configuration options in Dot NET Core using prefixed environment variables.

Conda is a package management system that is popular in the machine learning and python space.

Fix .NET installation on Linux for missing dotnet dependencies.

How to filter exclude logs for containers in EKS FluentBit CloudWatch plugin

Send emails using SMTP mailer in Python. Detailed tutorial for sending mail in Python.

How to Schedule a Text Message

How to Create Compelling Email Subject Lines to Increase Open Rates

How to Check Your Domain Reputation?

HTML entities NBSP in emails

Did you know you can send and receive emails using GraphQL?

How to create real email addresses using GraphQL to send and receive emails in tests and frontend applications.

What are common SMTP mail server ports and how do you find them?

How to set GitHub CLI token in terminal without a file

Test applications with real emails. MailSlurp is like a fake email account.

Generate random emails in code or visual dashboard.

Handle response exceptions with Fetch in Javascript

Modern typescript tooling has come a long way. See how to setup a new project with TS-Node, TSC, and typeconfig.json.

Fake email accounts for QA testers and developers

Extensive Information on LDAP

Explaining Cloud Email with Options to Think About

Email verification and deliverability testing with MailSlurp

Send bulk transactional emails with MailSlurp online or in code using CSharp, Node.js, Java, PHP and more.

Test email accounts for email testing. Alternatives to Mailinator, MailTrap, Mailosaur and more.

Email MIME type message attachment file size limits and conventions

What are the rules for email address matching. Are they case sensitive or insensitive?

10 quick tips for testing an email before you send it.

Can emails be sent over blockchain? Well kind of! LedgerMail and other and at the cutting edge of decentralized email.

Fake email account generator for testing and development. Create real email accounts.

Email Bounces: What to Do About Them?

APIs for email marketing and social campaign testing. Send, receive, validate and test emails in code and online.

Hosted email domains for custom mail servers

Create cross platform build scripts for DotNET Core in a way similar to Makefiles.

Do's and Don'ts for multiple SPF records

Sending transactional emails with AWS is more powerful than other API providers but comes with some downsides.

Create real throw-away email addresses for testing and development in .NET core. Follow this guide to get started.

Determining When to Send Emails to Increase Open Rates, Click Rates, and Sales?

Detailed Instructions for Fixing the 550 XXX Error

Easily deploy a self-hosted Redash instance to an AWS EC2 machine using Terraform.

Create and publish OpenAPI Java clients using Gradle and Maven S3

DotNet starter project MVC generation using the command line interface.

Email can spam regulations for better sender reputation.

How to maintain a strong sender reputation and delivery when cold emailing

An introduction to cloud email APIs

Add gifs to emails for more engagment

CC and BCC in SMTP

Best SMS apps for android

Best 4 frameworks for evaluating web-based applications

Avoiding Spam Filters

How to create API libraries for your DotNET project using SwashBuckle Swagger annotations and build-time client generation

Authentication vs. Authorization: What You Need to Know About These Security Processes

All you need to know about smtp4dev

All You Need To Know About Content Marketing

Affiliate Marketing: What it is and How to Start Using it

A fake SMTP server setup for testing.

1111 SMTP Connections failing