Email Validation API
POST /v1/email-validation — verify deliverability with SMTP + engagement signals.
Validate Email
Verify email addresses with industry-leading accuracy. Our validation system combines SMTP verification with engagement data for the most reliable results.Endpoint Details
- Pricing
- Rate Limits
| Metric | Value |
|---|---|
| Cost | 0.25 credits per validation |
| Calculation | 4 validations = 1 credit |
| Free Results | unknown and RFC-invalid results are free |
invalid and returned instantly — no credits charged. This includes malformed addresses, invalid characters, and improper formatting.Quick Example
Request Parameters
Response
valid, invalid, or unknownvalid/invalid, 0 for unknown)Example Response
Status Codes
valid
invalid
unknown
RFC Compliance
Emails that don’t comply with RFC 5321/5322 standards are automatically markedinvalid — no credits charged:
| RFC Violation | Example | Result |
|---|---|---|
Missing @ symbol | johnleadmagic.io | invalid (FREE) |
| Invalid characters | alex @example.com | invalid (FREE) |
| Missing domain | alex@ | invalid (FREE) |
| Double dots | john..doe@leadmagic.io | invalid (FREE) |
| Invalid TLD | alex@leadmagic | invalid (FREE) |
Success Messages
| Message | Status | Cost |
|---|---|---|
Email is valid. | valid | 0.25 |
Email is invalid. | invalid | 0.25 |
Email is invalid (RFC non-compliant format). | invalid | FREE |
Email is invalid (malformed address). | invalid | FREE |
Unable to determine email validity. | unknown | FREE |
Best Practices
Pre-validate format client-side
Pre-validate format client-side
Validate before sending campaigns
Validate before sending campaigns
Handle unknown results
Handle unknown results
unknown results, consider retrying later or using Email Finder to verify the specific address exists before adding to campaigns.Batch your validations
Batch your validations
Use response headers for monitoring
Use response headers for monitoring
X-Credits-Remaining so you can track spending without extra API calls.Use Cases
List Cleaning
Form Validation
CRM Hygiene
Lead Scoring
Authorizations
Your LeadMagic API key. Header name is case-insensitive (X-API-Key, X-API-KEY, x-api-key all work).
Body
Email address to validate
"alex.rivera@example.com"
Response
Successful validation
"alex.rivera@example.com"
"valid"
0.25
"Email is valid."
"mx1.example.com"
"Example Mail"
Security gateway vendor name
null
Security gateway type
null
false
"Leadmagic"
"Internet"
"11-50"
2022
"Private"
Legacy field name for the B2B company profile.
"linkedin.com/company/leadmagichq"
"75153174"
null
null