# SMTPing

> SMTPing is the most advanced email verification and deliverability platform on the market. We classify every address into one of 13 verdict types, including spam traps, complainers, disposables, catch-alls, blacklisted, and spambots, so senders know exactly what they are mailing before they send.

Founded 2022 · Wyoming, USA · SOC 2 Type II + ISO 27001 certified · GDPR-aligned.

The 13 verdict types are central to our product. Each has a dedicated detail page with deep explanation, detection methodology, examples, and FAQ. We also offer single-purpose verifier tools (Free, Catch-all, Spamtrap, Disposable, Spambot), bulk CSV processing up to 100,000 emails per batch, and a real-time REST API with sub-100ms response times. Adjacent products include Blacklist Monitor (82 sources, sub-5-minute alert latency) and Mail Tester (pre-send scoring across 40+ checks).

## Products

- [Email Verification](/email-verification): The pillar product. 13-verdict classification engine, bulk and real-time.
- [Blacklist Monitor](/blacklist-monitor): Track domains and IPs across 82 blocklists with real-time alerts and a delisting playbook.
- [Mail Tester](/mail-tester): Score outbound messages on authentication, content, links, and reputation before send.

## Verifier tools

- [Free Email Verifier](/free-email-verifier): Single-address full 13-verdict pipeline. 5 free checks daily (1 per minute), no card.
- [Catch-all Verifier](/catchall-email-verifier): Behavioral scoring to upgrade catch-all to valid catch-all.
- [Spamtrap Verifier](/spamtrap-email-verifier): Scan against our 150M-entry continuously-updated trap database.
- [Disposable Email Checker](/disposable-email-verifier): 3,500+ throwaway services + novel-domain detection.
- [Spambot Verifier](/spambot-email-verifier): Identify security gateway scanners and fraud bots.
- [SMTP Error Code Checker](/smtp-error-code-checker): Decode any 4xx or 5xx bounce line.

## The 13 verdict types

- [Valid](/valid-emails): Confirmed deliverable. Full pipeline pass.
- [Valid catch-all](/valid-catchall-emails): Catch-all domain, behavioral signals confirm address is real.
- [Catch-all](/catchall-emails): Catch-all domain, insufficient signal to confirm.
- [Alias](/alias-emails): Plus-addresses, forwarders, role accounts. Real human behind a layer.
- [No-reply](/no-reply-emails): noreply@, donotreply@, valid mailbox, no one reads.
- [Full inbox](/full-inbox-emails): Mailbox over quota; rejecting new mail.
- [Invalid](/invalid-emails): Syntax, MX, or mailbox-existence failure. Guaranteed bounce.
- [Unknown](/unknown-emails): Verification could not complete. Never charged.
- [Disposable](/disposable-emails): Throwaway services (Mailinator, 10MinuteMail, etc).
- [Complainer](/complainers-emails): Documented history of spam-reporting commercial mail.
- [Spamtrap](/spamtraps-emails): Honeypot addresses operated by ISPs and anti-spam orgs.
- [Spambot](/spambots-emails): Automated openers (security gateways, fraud bots).
- [Blacklisted](/blacklisted-emails): Address or hosting domain appears on one or more blocklists.

## Pricing

- [Pricing](/pricing): Pay-as-you-go credit packs (one-time) or subscription (monthly/annual). All plans include the full 13-verdict engine.
- [Lifetime Deal](/lifetime-deal): Available until December 31, 2026. Five bundles from $99 to $999 with lifetime credits and lifetime access. Email verification only.

## Resources

- [How it works](/how-it-works): The 7-stage pipeline, infrastructure, integration patterns.
- [Case Studies](/case-studies): Five real teams, their challenges, and what changed.
- [Industries](/industries): How SMTPing fits B2B SaaS, e-commerce, cold outbound, agencies, healthcare, fintech, and non-profits.
- [Guides](/guides): Deliverability fundamentals, technical setup (SPF/DKIM/DMARC/BIMI), list hygiene, recovery, cold-outbound.
- [Integrations](/integrations): Native apps + webhooks + SDKs for Smartlead, Lemlist, Instantly, HubSpot, Salesforce, Pipedrive, Klaviyo, Mailchimp, Zapier, Make, n8n, and more.
- [FAQ](/faq): 30+ questions organized by category.
- [Sitemap](/sitemap): Full index of every page on the site.

## Pillar guides

- [Deliverability primer](/deliverability-primer-guide): SPF, DKIM, DMARC, reputation, list quality from first principles.
- [Inbox vs Promotions vs Spam](/inbox-vs-promotions-vs-spam-guide): What decides tab placement at Gmail, Outlook, Yahoo.
- [Land in primary](/land-in-primary-content-guide): Content, engagement, and formatting patterns that stay out of Promotions.
- [Sender score explained](/sender-score-explained-guide): How mailbox providers score you and how to improve fast.
- [Reputation rebuilding, 90 days](/reputation-rebuilding-90-days-guide): Post-damage cadence and segmentation plan.
- [Reputation monitoring explained](/reputation-monitoring-explained-guide): The five sources that matter and the alert stack.
- [SPF, DKIM, DMARC setup](/spf-dkim-dmarc-setup-guide): Step-by-step DNS walkthrough with copy-paste records.
- [DMARC for the first time](/dmarc-first-time-guide): Moving safely from p=none to quarantine to reject.
- [BIMI + VMC setup](/bimi-vmc-setup-guide): Getting your logo in the inbox across Gmail, Yahoo, Apple Mail.
- [List-Unsubscribe one-click (RFC 8058)](/list-unsubscribe-one-click-guide): The header now required for bulk senders.
- [Sending domain & subdomain strategy](/sending-domain-subdomain-strategy-guide): Why not to send from your apex, and how to isolate.
- [Google Postmaster Tools](/google-postmaster-tools-guide): Every metric and threshold that matters.
- [Microsoft SNDS](/microsoft-snds-guide): Colour scores, trap-hit thresholds, JMRP setup, recovery playbook.
- [Spamhaus DBL delisting](/spamhaus-dbl-delisting-guide): Root cause, appeal templates, timeline.
- [Hard vs soft bounces](/hard-bounces-vs-soft-bounces-guide): Why one matters far more and how to act.
- [SMTP error codes](/smtp-error-codes-guide): 4xx and 5xx reference with recommended actions.
- [First list clean](/first-list-clean-guide): What to expect on a typical un-cleaned list.
- [Re-verification cadence](/re-verification-cadence-guide): How often to clean by list type.
- [Suppression list management](/suppression-list-management-guide): Schema, GDPR interaction, cross-ESP portability.
- [Catch-all domains](/catchall-domains-guide): The 18% of B2B other validators give up on.
- [Spamtraps in depth](/spamtraps-in-depth-guide): Pristine, recycled, typo, role. How to avoid each.
- [Avoiding complainer verticals](/avoiding-complainer-verticals-guide): Industries with structurally high complaint rates.
- [Email warmup best practices](/email-warmup-best-practices-guide): 28-day ramp, engagement targets, honest limits.
- [Mailbox rotation for cold outbound](/mailbox-rotation-cold-outbound-guide): Volume distribution and rotation cadence.
- [Sequence cadence 2026](/sequence-cadence-2026-guide): Modern send-day/hour patterns for cold sequences.
- [Engagement segmentation](/engagement-segmentation-guide): Segments that protect reputation.
- [Re-engagement campaigns](/re-engagement-campaigns-guide): Reviving dormant subscribers without hitting traps.
- [13 verdict types explained](/13-verdict-types-guide): Every verdict with action recommendations and edge cases.
- [Feedback loops setup](/feedback-loops-setup-guide): Complaint routing across major mailbox providers.
- [Compliance digest](/email-compliance-digest-guide): GDPR + CAN-SPAM + CASL + PECR in one reference.
- [Cold email legality](/cold-email-legality-guide): Regulatory posture by jurisdiction and use case.

## Company

- [About](/about): Our story, team, values, milestones.
- [Contact Us](/contact): Email, chat, scheduled call. One-business-day response.
- [Status](https://status.smtping.com): System uptime and incident history.
- [Changelog](/changelog): Product updates, new verdicts, infrastructure improvements.

## Legal

- [Terms & Conditions](/terms): Acceptance, prohibited uses, payment, liability.
- [Privacy Policy](/privacy): What we collect, how we use it, how we share it.
- [GDPR Policy](/gdpr): Lawful basis, rights, transfers, supervisory authority.
- [Cookie Policy](/cookies): Essential, preferences, analytics, marketing cookies.
- [Refund Policy](/refund): 30-day money-back guarantee for all plans.
- [Data Processing Agreement](/dpa): Controller-processor terms, SCCs, subprocessors.

## Programs

- [Startups](/startup-program): Discounted plans for early-stage teams.
- [Non-profits](/nonprofit-program): 30% off for verified 501(c)(3) organizations.
- [Educational Institutions](/educational-program): Discounted Lifetime bundles for accredited schools.

## Developers

- API documentation: https://smtping.com/docs
- Status page: https://status.smtping.com
- System uptime SLA: 99.99%
- API median latency: 58ms (p95: <100ms)
- SDKs: Node, Python, Ruby, Go, PHP (official); Rust, .NET (community)
- Webhooks: HMAC-SHA256 signed, sub-second delivery, retry with backoff
- Bulk processing: up to 100,000 emails per batch, ~60–90 minutes to complete

## Contact

- General: hello@smtping.com
- Sales: sales@smtping.com
- Support: support@smtping.com
- Legal: legal@smtping.com
- Privacy / DPO: privacy@smtping.com / dpo@smtping.com
- Security: security@smtping.com
- Address: SMTPing, 1712 Pioneer Avenue, Suite 1000, Cheyenne, WY 82001, USA
- EU representative: SMTPing, 128 boulevard Jean Jaures, Paris 75019, France