WillItInbox
WillItInbox is an email deliverability and validation platform for SaaS teams, developers, agencies, marketers, and newsletter operators that depend on outbound email.
Teams can generate a unique test inbox, send a real message from their app or ESP, and receive a practical deliverability report across SPF, DKIM, DMARC, BIMI, DNS, reverse DNS, blocklists, TLS, headers, content, links, reputation, and sender infrastructure.
WillItInbox also validates individual emails and bulk CSV lists using syntax, DNS/MX, disposable, role, typo, provider, catch-all, SMTP, suppression, and confidence signals. It includes domain monitoring, DMARC report analysis, sending source visibility, provider reputation checks, API keys, webhooks, scheduled checks, incident diagnostics, inbox placement checks, team workspaces, and exportable reports.
Paid plans start at $39/month. PAYG credits are available for extra email validation and deliverability testing usage.
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Bouncer
Bouncer - The easiest to use yet the most powerful E-mail Validation and Deliverability Service.
Bouncer is a fortress-like secure (GDPR compliant) Email Verification and Deliverability platform trusted by thousands of companies across 6 continents. Founded in 2017, Bouncer helps businesses improve human-to-human email communication by ensuring every message has the best chance of reaching the inbox.
Bouncer is a technological leader in email verification.
Both list and API verification are top-notch, backed by a zero-downtime policy, industry-leading coverage, and high performance (up to 200,000 verified emails per hour per customer). Beyond verification, Bouncer helps protect signup forms with Shield, automates list hygiene with AutoClean, improves inbox placement with Deliverability Kit, detects risky addresses with Toxicity Check, and connects seamlessly with a growing library of integrations.
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ZeroBounce
ZeroBounce is an email verification, scoring and deliverability platform helping businesses improve their inbox placement. The service detects email typos, nonexistent and abusive email accounts, spam traps and other risky email addresses.
ZeroBounce also provides an email scoring service and a suite of deliverability tools to further enhance email inbox placement. The company operates a military-grade security infrastructure, ensuring customer data is protected at the highest levels.
With more than 23 billion emails validated to date, ZeroBounce serves 400,000+ businesses in 190+ countries and adds up to 200 new clients every day. Companies using email lists validated by ZeroBounce report a 99%+ accuracy rate and maintain a good sending reputation. In 2019, ZeroBounce took no. 851 on the Inc. 5000 list of the fastest-growing private companies in the United States. In 2020, ZeroBounce rose to no. 40 on the list. In 2021, ZeroBounce was number 9 on the Inc. 5000 Regionals list.
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InboxStack
InboxStack is an email deliverability intelligence platform built around Brain, a proprietary causal AI engine that identifies why emails miss the inbox — not just that they did. Most deliverability tools stop at monitoring: they show a drop in inbox placement or a blocklist hit and leave you to investigate. InboxStack goes further, correlating signals from your ESP, DNS authentication records (SPF, DKIM, DMARC), Google Postmaster Tools, Microsoft SNDS, and 50+ blocklists through a causal knowledge graph built on a 22-year deliverability knowledge base — tracing the actual root cause, whether it's a DKIM misalignment, IP reputation dip, or content trigger.
Onboarding starts with forwarding your email headers for an instant DNS/auth audit, no migration required. Teams that want ongoing monitoring can connect their ESP and Postmaster accounts, with optional seed testing for real inbox-vs-spam placement data.
Built especially for digital agencies and ESP's.
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