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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.

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.

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.

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

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.

Get US-IP Google & Microsoft Workspace accounts from $2.5. 95% inbox delivery. Works with SmartLead, Instantly, Lemlist, SalesForge, Warmy & more.

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

The InboxSDK is a high level Javascript library used to easily build browser extensions that interact with both Gmail and Inbox by Google. It provides all of the necessary APIs to create full-fledged applications directly inside Gmail and Inbox. Because the SDK is fully maintained and evergreen, you’ll never be forced to maintain your app.

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 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.

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

SafeTemp.email lets you create free disposable temporary email addresses (temp mail) in seconds. Receive verification emails anonymously, block spam, and protect your real inbox. No signup required.

Get a free disposable email address with Temp Mailin. Instantly receive emails, block spam, and protect your privacy. No registration needed.

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.

DMARC (Domain-based Message Authentication, Reporting & Conformance) helps protect your domain from email spoofing and phishing. When you enable DMARC on your domain, email providers like Gmail, Outlook, and Yahoo send you aggregate reports showing: - Who's sending email claiming to be from your domain - Which emails passed or failed authentication (SPF/DKIM) - How many emails were sent, and from which IP addresses - Whether malicious actors are trying to impersonate your domain The Problem: These reports arrive as compressed XML attachments in your inbox - nearly impossible to read or analyze manually. The Solution: Parse DMARC automatically fetches these reports from your inbox, parses them, and displays everything in a beautiful dashboard. All in a single 14MB Docker image.

MIA (Marketing Inbox Assistant) uses AI to automatically process marketing email responses, instantly routing high-intent leads to sales and handling compliance requests like opt-outs. It enriches your database from email signatures and out-of-office replies while supporting 60+ languages. MIA integrates with major platforms like Marketo, HubSpot, Salesforce, Google, and Outlook to eliminate manual inbox management.

KokoQuest helps users discover and build lists of real companies that match highly specific business criteria. It supports natural-language searches for manufacturers, suppliers, service providers, partners, or customers, and returns ranked company lists with relevance scoring. KokoQuest covers the full workflow from company discovery to contact enrichment and email drafting, allowing users to go from search intent to outreach-ready leads in one place. Through its Gmail integration, the AI can translate a user’s intent into a ranked list of relevant companies, automatically enrich each with contact details, and draft a personalized email ready to send directly from Gmail. Unlike static lead databases, KokoQuest is designed for niche and hard-to-define markets where coverage is inconsistent or incomplete. It is useful for finding regional providers, contract manufacturers, private-label partners, and specialized B2B services that are often missing from traditional sales tools.

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

MailArmor is an AI-powered email security platform for SMBs in India. It integrates with Microsoft 365 in 5 minutes, complies with CERT-In & DPDP, and protects against phishing, malware, and BEC. ₹150/user/month. Free trial.

Aepto is an AI-powered domain monitoring platform built to give full visibility and control over domains spread across multiple providers. Instead of logging into separate registrar, hosting, and email dashboards, Aepto centralizes everything into one clean interface and continuously monitors domain health using public signals and AI analysis. Once a domain is added, Aepto automatically scans the registrar, hosting setup, email configuration, pricing, and renewal details—no APIs or integrations required. It monitors email deliverability, DNS records, website and subdomain uptime, content changes, and suspicious activity such as nameserver changes or lock status updates. When something goes wrong, Aepto alerts you early and clearly explains what happened and which provider to contact. Aepto also helps track domain expenses, visualize spending, assign ROI, organize domains into folders, and customize pricing and provider details when needed. Advanced features include AI-powered domain discovery, domain watch for tracking expiring domains you don’t own, distributed uptime monitoring, and customizable white-labeled status pages with incidents and maintenance updates. Designed for businesses, agencies, and teams that rely on domains for live websites, email, and APIs, Aepto focuses on proactive monitoring and clarity—so nothing breaks silently and small issues don’t turn into bigger problems.

Tempemail.cc is a free online service designed to provide users with temporary, disposable email addresses. Its primary function is to protect your primary inbox from spam, marketing emails, and potential privacy risks by acting as a buffer between your real identity and various online services.

Outreach Box is an AI-powered sales engagement, marketing automation and email outreach platform designed to help businesses find warm leads, scale outreach campaigns, and close more deals. With intelligent automation, unlimited email outreach, advanced deliverability, AI-generated personalized solution, and real-time campaign analytics, Outreach Box enables sales and marketing teams, agencies, and marketers to increase business reach and automate daily works for better output.

Ark is the AI first email API. Send transactional emails with native MCP support, sub-second delivery, and 99.9% deliverability.

You keep checking your inbox—just in case. OWL lets you stop. Get push alerts for the VIP emails you define. Everything else can wait.

Mailwarm is an automated email warmup and deliverability platform designed to help businesses keep their emails out of spam folders and consistently reach the inbox.

The world's most reliable inbox architecture for cold email teams sending 100k+ monthly. Zero configuration. Total deliverability control.

Capture and inspect emails in development without sending to real users. SMTP sandbox with team collaboration, secure encryption, and responsive previews.

Email Deliverability Solutions (Analytics + Managed Services). We’ve helped 16,000+ companies like TikTok & HSBC land over 30B emails in customer inboxes.

A complete suite of deliverability tools & services makes it easy to get back in the inbox.

(formerly Clawdbot) - AI that does things. Manages inbox, emails, calendar via WhatsApp, Telegram, Discord. Open source.

Your inbox, organized. Your replies drafted. Your day, under control. With Pullsy's Ai

An AI-powered email client that instantly cuts your inbox in half, provides an AI Personal Assistant, Extracts key information, manages tasks and more

Postigo is an advanced email delivery and outreach platform designed to solve the technical challenges of cold email routing and sender reputation management. For growth engineers, marketing ops, and sales operations teams, maintaining high deliverability while scaling outbound campaigns often requires complex IP warming and constant monitoring of spam trap triggers. Postigo abstracts this complexity by providing out-of-the-box, fully warmed-up SMTP servers paired with an AI-driven content generation engine. By dynamically generating unique, personalized email payloads at scale, Postigo prevents campaigns from being flagged by algorithmic spam filters that detect repetitive content. With an emphasis on reliability and compliance, Postigo fits seamlessly into modern sales and marketing stacks, allowing teams to focus on campaign logic rather than underlying email infrastructure.

MailMoxie is your platform to identify and fix email deliverability issues. Test emails against 50+ spam triggers, analyze DNS records, and get expert deliverability consulting to ensure your emails reach the inbox, not the spam folder.

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.

Free email deliverability checker for B2B outreach. Validate email addresses instantly, check MX records, detect role-based emails, and improve inbox placement before your cold email campaigns.

Consul is an AI-powered executive assistant that handles your email, calendar, and scheduling end-to-end. It triages your inbox, drafts replies in your voice, books meetings without the back-and-forth, and delivers a personalized daily brief before your first coffee. Available via web, email, and iMessage, Consul works around the clock so nothing slips through the cracks.

It is an all-in-one email deliverability platform to supercharge your email performance. Locate, solve, prevent email deliverability pitfalls, and become a credible sender for any ESP provider.

It is an Email Tracking for Gmail and GSuite, adds the double check marks to your mail if it is read by recipient (Just like WhatsApp), Receives real-time pop-ups notification on your desktop when your emails are opened.

It is an advanced MTA built to handle the most critical reliability, performance, security, and deliverability requirements.