How qualification works

Pipeline overview#

When a lead arrives in Zero Bad Leads, it automatically goes through a 5-step verification pipeline. Each step analyzes a different aspect of the lead and contributes to the final score.

The complete pipeline takes on average 2 to 5 seconds per lead.

Email validation

The first verification analyzes the lead's email on three levels:

Format: checks whether the email follows the correct pattern (e.g., user@domain.com).

MX records: queries the domain's DNS records to confirm it accepts emails. If the domain has no MX records, the email is marked as invalid.

Disposable email detection: checks whether the domain belongs to a temporary email service. Disposable emails are a strong indicator of low-quality leads.

Most commonly detected disposable domains:

Domain	Type
`mailinator.com`	Disposable
`guerrillamail.com`	Disposable
`tempmail.com`	Disposable
`throwaway.email`	Disposable
`yopmail.com`	Disposable
`10minutemail.com`	Disposable
`trashmail.com`	Disposable
`sharklasers.com`	Disposable
`dispostable.com`	Disposable
`maildrop.cc`	Disposable

The list of disposable domains is continuously updated. In addition to the domains listed, the platform detects hundreds of other temporary email services.

Result: the email receives the status valid, invalid, or risky.

Phone validation

The second verification analyzes the phone number:

E.164 format: the number is normalized to the international E.164 standard (e.g., +5511999999999). The platform accepts various input formats:

Input format	Result
`(11) 99999-9999`	`+5511999999999`
`11999999999`	`+5511999999999`
`+55 11 99999-9999`	`+5511999999999`
`5511999999999`	`+5511999999999`

Country code detection: when the country code is not provided, the platform defaults to +55 (Brazil).

Format validation: checks whether the number has the correct number of digits for the detected country.

Result: the phone receives the status valid or invalid.

CNPJ verification

If the lead contains a CNPJ field, the platform queries the BrazilAPI to obtain up-to-date information:

Verified data	Description
Status	Whether the CNPJ is active, suspended, or closed
Legal name	Official company name
Trade name	Commercial name
Company size	Micro, small, medium, or large enterprise
Primary activity	CNAE economic activity code
Incorporation date	When the company was established
City/State	Company location

CNPJ verification depends on BrazilAPI availability. If the service is temporarily unavailable, the lead proceeds through the pipeline without this verification, and the cnpj_valid field remains null.

Result: the CNPJ receives the status valid (active) or invalid (closed/suspended/nonexistent).

IP analysis

If the visitor's IP is captured, the platform queries ProxyCheck.io to assess the risk:

Verification	What it detects
Proxy	Whether the IP is using a proxy service
VPN	Whether the IP is using a commercial VPN
Risk score	Score from 0 to 100 indicating risk level
Type	Residential, datacenter, mobile, educational
Country	IP's country of origin

Datacenter IPs, proxies, and VPNs are indicators of potentially fraudulent leads or bots.

Result: the fields ip_risk_score (0-100), ip_proxy (true/false), and ip_vpn (true/false) are populated.

To capture the visitor's IP, your form needs to include the IP in the webhook payload. Many platforms (such as RD Station and HubSpot Forms) do this automatically.

AI Scoring (Google Gemini)

The final step is the most powerful. The artificial intelligence analyzes all data collected in the previous steps and generates a score based on your ideal lead profile.

Gemini evaluates:

Email suitability: corporate domain vs. free (gmail, hotmail)
Phone quality: valid number with correct format
Company data: size, segment, location (via CNPJ)
Job title: decision-making level and relevance
IP risk: proxies, VPNs, datacenters
Custom signals: specific criteria you defined in the scoring profile

Final result:

Score	Classification	Action
80-100	Hot	Highly qualified lead
60-79	Warm	Lead with good potential
40-59	Cold	Lead with low potential
0-39	Unqualified	Discarded lead

The classification and score thresholds can be customized in the scoring profile. The values above are the defaults.

Complete flow#

Lead received via webhook
    │
    ├── 1. Email validation
    ├── 2. Phone validation
    ├── 3. CNPJ verification (if available)
    ├── 4. IP analysis (if available)
    └── 5. AI Scoring
         │
         ├── Score >= threshold → Status: "qualified"
         │   └── Sent to outbound integrations
         │
         └── Score < threshold → Status: "skipped"
             └── Available in logs for review

What is included in all plans#

All verifications described above are included in all plans (Starter, Pro, and Scale):

Email validation (format + MX + disposable detection)
Phone validation (E.164 format)
CNPJ verification (BrazilAPI)
IP analysis (ProxyCheck.io)
AI Scoring (Google Gemini)

There is no additional charge per verification. You only pay for the number of unique qualified leads per month.

Next steps#

Configure your scoring profile to customize the qualification criteria
Explore ready-made templates to get started quickly with a pre-configured profile