Use Case

Know If It's a Decision-Maker or a Gmail

Your sales team spends hours on leads that turn out to be personal emails, generic inboxes, or catch-all black holes. One API call tells you which leads are worth the call.

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The Problem

The Hidden Cost of Bad Lead Data

30-40%

of form submissions use personal email

12 min

avg time wasted per unqualified lead

info@

role addresses that never convert

The difference between sarah@stripe.com on Google Workspace and info@newstartup.io on a 2-week-old domain is the difference between a pipeline deal and a dead lead. MailSentry tells you which is which.

How It Works

Four Signals That Separate Real Leads from Noise

Free Provider Detection

Instantly distinguish personal Gmail/Yahoo from business domains. The is_business field tells you if the domain uses Google Workspace, Microsoft 365, or Zoho — even on custom domains. B2B vs B2C in one field.

Role-Based Detection

Flag generic addresses like info@, admin@, sales@. The role_type field returns the exact prefix so you can build segmented logic — route sales@ to one flow, support@ to another.

MX Provider Intelligence

The mx_provider field reveals the email hosting behind any domain. 'Google Workspace' on a custom domain = established business. Self-hosted mail on a 2-week domain = proceed with caution.

Domain Age

How long has this company existed? age_days: 25 with risk_flag: newly_registered tells your scoring model this isn't an established business yet.

See It in Action

Two Leads. One API Call Each. Different Stories.

Lead A — sarah@stripe.comScore 95

{
  "score": 95,
  "verdict": "valid",
  "checks": {
    "free_provider": {
      "is_free": false,
      "is_business": true,
      "mx_provider": "Google Workspace"
    },
    "role_based": {
      "is_role_based": false,
      "role_type": null
    },
    "domain_age": {
      "age_days": 5942,
      "risk_flag": null
    }
  }
}

Lead B — info@newstartup.ioScore 38

{
  "score": 38,
  "verdict": "risky",
  "checks": {
    "free_provider": {
      "is_free": false,
      "is_business": true,
      "mx_provider": "Zoho Mail"
    },
    "role_based": {
      "is_role_based": true,
      "role_type": "info"
    },
    "domain_age": {
      "age_days": 25,
      "risk_flag": "newly_registered"
    }
  }
}

Lead A: verified business email on a 16-year-old domain. Route to sales immediately. Lead B: generic inbox on a 25-day-old domain. Nurture, don't call.

Implementation

const result = await fetch('/api/v1/verify', { ... })

const priority = !result.checks.free_provider.is_free
  && result.checks.free_provider.is_business
  && !result.checks.role_based.is_role_based
  && result.score >= 80

// priority = true → route to sales. false → nurture sequence.

Compare

B2B Lead Scoring: Beyond the Boolean

Feature	MailSentry	ZeroBounce	Kickbox
Free/business detection	is_free + is_business + mx_provider	Boolean only	Boolean only
Role-based classification	role_type (info, admin, sales...)	Boolean flag	Boolean flag
MX provider identification	30+ providers mapped	Not available	Not available
Domain age	age_days + risk_flag	Not available	Not available
Catch-all confidence	0-1 score	Flag only	Flag only
Free plan	1,000/mo recurring	100/mo	100 one-time