Ark

Dependal is transactional email infrastructure for B2B SaaS. Verified domains, enforced suppressions, throttles and clear logs — built to protect sender reputation.

Don't stress over Amazon SES or get banned by SendGrid. Transmit gives you Postmark-level happiness with the power of AWS. Start sending in minutes.

Twilio SendGrid's cloud-based email infrastructure relieves businesses of the cost and complexity of maintaining custom email systems. Twilio SendGrid provides reliable delivery, scalability & real-time analytics along with flexible API's.

Amazon SES eliminates the complexity and expense of building an in-house email solution or licensing, installing, and operating a third-party email service. The service integrates with other AWS services, making it easy to send emails from applications being hosted on services such as Amazon EC2.

Mailgun is a set of powerful APIs that allow you to send, receive, track and store email effortlessly.

Mandrill is a new way for apps to send transactional email. It runs on the delivery infrastructure that powers MailChimp.

It is a single module with zero dependencies – code is easily auditable. The email delivery is Secure using TLS/STARTTLS. You can use HTML content, as well as plain text alternative.

Postmark removes the headaches of delivering and parsing email for webapps with minimal setup time and zero maintenance.

Mailjet is a real-time Cloud Emailing platform: scalable, agile and flexible. Our unique algorithm boosts your deliverability and our platform provides in-depth insight so you can optimize more than ever.

It is a free and open-source mail transfer agent that routes and delivers electronic mail. It is Wietse Venema's mail server that started life at IBM research as an alternative to the widely-used Sendmail program. Now at Google, Wietse continues to support it.

SparkPost is the world’s #1 email delivery provider. We empower companies with actionable, real-time data to send relevant email to their customers which increases engagement and both top and bottom line revenue.

We offer one platform that covers all email-related needs in one place: testing, sending, and in-depth tracking to control how email infrastructure works and performs.

It is a modern email sending platform focused on providing the best developer experience. Build, test, and deliver transactional emails at scale.

Send email from your app with a simple API call, Sendwithus manages the rest. Templates, testing, data management, segments, and analytics are all accessible through a friendly dashboard.

It is an open source IMAP and POP3 email server for Linux/UNIX-like systems, written with security primarily in mind. It is an excellent choice for both small and large installations. It's fast, simple to set up, requires no special administration and it uses very little memory.

It adds scheduled sending and the easiest, most integrated email reminders to Gmail, helping you reach Inbox Zero.

A new kind of transactional email service designed for developers to work faster and smarter with a powerful infrastructure to scale quickly.

It is a premium email delivery and email relay solution that enables you to send and track high volume emails effortlessly. Integrate and start sending in minutes.

Postal is a complete and fully featured mail server for use by websites & web servers. Think Sendgrid, Mailgun or Postmark but open source and ready for you to run on your own servers. Postal was developed by aTech Media to serve its own mail processing requirements and we have since decided that it should be released as an open source project for the community.

250ok is an email deliverability tools company that produces a Software‐as‐a‐Service (“SaaS”) platform to monitor and measure the deliverability of email networks. These networks consist of companies sending various forms of messages including marketing, transactional, share, and others from various platforms.

Free AI invoice generator for freelancers. Create professional PDF invoices in 30 seconds with AI — 50+ currencies, smart autofill, no signup, no watermark. Send, track & auto-remind for free.

It is an email delivery service for your transactional and marketing emails. It replaces your email infrastructure so you don’t have to build, scale, and maintain these systems in-house. With an easy SMTP service you can start quickly, while our robust API gives you full control over email processing and reporting. Your transactional emails are delivered instantly and your marketing campaigns can be scaled to millions.

It helps build lasting business relationships, right from your inbox. A sales engagement platform designed for sales professionals and account managers.

Transactional emails are the forgotten step child of internet marketers. Apostle.io empowers marketers to manage transactional emails themselves, as they would their list based campaigns. Preview, Update, Analyse and Test your transactional email all in one place.

CloudMailin allows you to receive any volume of incoming email via a Webhook. You are given an email address that will forward any incoming message to your app, as an HTTP POST, within milliseconds. You can also seamlessly check the delivery status of each of your incoming emails via the dashboard, bounce emails that you do not wish to receive and use your own domain name.

It is the speedy transactional email delivery service that provides reliable Inboxing in less than a second, all with a very disruptive pricing model. Only pay for unopened emails.

Is an AI-driven multichannel outreach platform that reaches prospects where they're most active while keeping every message personal, timely, and effective.

It is an all-in-one tool for email deliverability to make your Email Channel Reliable. It raises your sender reputation by interacting with real people in any language and helps you to hit the inbox of your prospect. Full automation.

Pinpoint email issues before you hit "send". Secure your emails from malicious actors and ensure your email delivery to the inbox.

Your transactional email should NOT trigger spam or marketing filters. Flute Mail plugs into your existing API provider to properly isolate segments, boost inbox rates, and safely store your transactional email data.

Sidemail is an all-in-one email delivery platform for startups that makes sending emails simple. It has everything for delivering and managing emails – email API, transactional emails, email marketing and automation, contact management, no-code email editor, email templates, subscribe forms, and more. Perfect for teams & developers that want reliable deliverability without the bloat. We're based in the EU and GDPR compliant.

Free email verifier & checker to validate email addresses instantly. Reduce bounces and verify emails in real time.

Free email checker and email verification with 99.9% accuracy. Reduce bounces, protect sender reputation. 100 free email verification credits daily.

It offers a simple REST-based JSON API enabling you to thoroughly check and verify email addresses right at the point of entry into your system.

It is a fully self developed solution, truly innovative in several respects, particularly scalable and configurable. This messaging solution offers the entire range of mail services — SMTP, POP3, IMAP, WebMail (Desktop and Mobile versions) — includes List server, Logging, Reporting, and FTP Backup modules and provides various, flexible administration options (including a central Web administration interface — WebAdmin).

It helps new brands and startups build an audience while they focus on building a product

It is an easy way to manage your outgoing emails from your apps. From creating and sending your emails to monitoring and managing their stats, you can do really useful things with it without worried about time zone disaverage.

It is a self-hosted open-source application that provides a REST interface on top of any email account you have access to read and send emails. Combining these features would give you a similar email sending experience you'd get from a transactional email service.

Is an advanced email verifier tool and email validation solution to check email lists, remove invalid addresses, and improve email deliverability and campaign performance.

Protect your domain with Dmarclytics. Run free DMARC, SPF, and DKIM checks to stop spoofing, enhance email authentication, and improve deliverability with powerful monitoring tools.

Send transactional emails that land in the inbox. JetEmail's developer-friendly API and SMTP deliver reliable email with built-in spam protection.

Use AI to find prospects that need you, automatically craft personalized cold emails for each, and scale effortlessly

Receive HTML form submissions without server-side code. Form.taxi handles email notifications, spam filtering, file uploads and GDPR-compliant data storage.

Puzzle Inbox provides pre-warmed Google Workspace and Outlook 365 inboxes to help agencies and sales teams scale cold email outreach fast. Every inbox comes fully configured with SPF, DKIM, and DMARC — ready to send straight away. Trusted by 1,200+ clients with over 70,800 active inboxes deployed, starting from $0.35 per inbox.

Generates invoices from your Stripe payments and emails them directly to your customers. Same invoices, zero invoicing fees.

A dedicated RUA address, automated report processing, and 24/7 authentication analysis. Bulk sender compliance for outgoing compliance, and hosted mta-sts for incoming confidence.

Email verification API with 15+ checks: disposable detection, scam domain blocking, SPF/DMARC validation, risk scoring, alias detection, and free deliverability tools. 200 free validations/month.

The headless form backend built for developers and designers. Create forms your way, host anywhere. Get validation, webhooks, email notifications, and more with zero backend code.

✅ 7-layer email verification ✅ Checks MX records, SMTP, format & more ✅ Instant results in seconds ✅ 100% free to use ✅ Part of Jarvis Reach's B2B prospecting platform with 750M+ verified contacts Stop wasting cold emails on dead addresses. Verify before you send.

KenMail by Kenscio is a powerful email marketing platform and bulk email sender designed for high deliverability, personalization, and scalable campaign execution. Perfect for enterprise email marketing.