Free APIs
Free Email & messaging APIs
| Free tier | Docs | ||
|---|---|---|---|
Validate email syntax, MX records and disposable domains
Catch: Free plan has a small monthly quota | Free plan with monthly request allowance | API key | docs |
Find and verify email addresses
Catch: Credits shared between search and verification | Free plan: 50 free leads/month | API key | docs |
Email validation and deliverability scoring
Catch: Small monthly allowance; API key required | Free monthly validation credits | API key | docs |
Email address validation API
Catch: Non-commercial use | Free plan: 100 API requests/month | API key | docs |
| Free: 100 phone validations/month | API key | docs | |
| Free plan available | API key | docs | |
Transactional and marketing email, SMS API
Catch: Brevo branding on free-plan emails | Free plan: up to 300 emails/day | API key | docs |
Transactional email API
Catch: Free plan: limited domains and support | Free plan: 3,000 emails/month | API key | docs |
| Free plan: 6,000 emails/month, 200/day | API key | docs | |
Build bots that send and receive Telegram messages
Catch: Bot token from BotFather; flood limits apply | Free | API key | docs |
FAQ
What is the best free email & messaging API?+
Abstract Email Validation, Hunter Email Verifier, ZeroBounce are good places to start. Compare the free tiers and catches in the table; they differ mostly in limits and whether commercial use is allowed.
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