Free Email Verification APIs: Which One to Choose?

Invalid email addresses cost businesses time and money. Email verification APIs help reduce bounce rates, improve deliverability, and maintain list hygiene. Here's what to look for and which free APIs deliver.

Why Email Verification Matters

A 10% bounce rate can damage your sender reputation and get you blacklisted. Email verification catches typos, disposable addresses, and non-existent mailboxes before you send.

EmailVerify - Real-Time Email Validation

Validate email addresses with comprehensive checks: syntax validation, MX record verification, disposable domain detection, and role-based filtering. 1,000 free verifications per month.

curl -X POST https://freeapitools.dev/api/v1/email/verify \
  -d '{"email": "user@example.com"}'

# Response:
# {
#   "valid": true,
#   "deliverable": true,
#   "disposable": false,
#   "role_based": false,
#   "mx_found": true,
#   "score": 95
# }

View EmailVerify docs →

What Gets Checked

• Syntax validation: Ensures email follows RFC standards
• MX records: Verifies domain has mail servers configured
• Disposable detection: Flags temporary/throwaway email services
• Role-based filtering: Identifies generic addresses like info@, admin@
• SMTP verification: Checks if mailbox exists without sending

SpamCheck - Email Content Analyzer

Before you send, check your email content for spam triggers. Get a spam score, flagged words, and improvement suggestions. 2,000 free checks per month.

View SpamCheck docs →

Best Practices

Verify emails at signup, not after. Use double opt-in for additional confirmation. Regularly clean your list by removing hard bounces and unengaged subscribers.

Get Your API Key

Start verifying emails in minutes:

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