Email – Free-tier APIs
31 Free-tier APIs in the category Email. Free public web APIs that developers and AI agents can call. Entries come from the open public-apis list; each link was checked automatically (HTTP status) on the date shown, which says the site responded, not that the API is good.
Best Temp Mail
Disposable inboxes for automated email testing, with OTP extraction
Cloudmersive Validate
Validate email addresses, phone numbers, VAT numbers and domain names
Disban
Classify email domains as disposable, free, alias, testing or parked to block fake signups
Disify
Validate and detect disposable and temporary email addresses
DropMail
GraphQL API for creating and managing ephemeral e-mail inboxes
Email Spam Tester
Send a test message and get a spam score, 41 checks with RFC citations and a fix plan
Email Validation
Validate email addresses for deliverability and spam
Email Validator by LifeStep
Validate email syntax and MX, detect disposable/role addresses, suggest typo fixes
EmailJS
Send emails directly from client-side JavaScript without a backend server
Guerrilla Mail
Disposable temporary Email addresses
ImprovMX
API for free email forwarding service
inboxsink
Disposable inboxes for end-to-end tests that wait for the email and extract OTP codes
Kickbox
Email verification API
mail.gw
10 Minute Mail
mail.tm
Temporary Email Service
mailboxlayer
Email address validation
MailboxValidator
Validate email address to improve deliverability
MailCheck.ai
Prevent users to sign up with temporary email addresses
Mailfornet
Disposable inboxes for end-to-end signup tests, with long-polling and HMAC-signed webhooks
MailRambo
Verify email deliverability with a strict yes/no, disposable and catch-all detection
MailSenpai DNS Check
Check a domain's SPF, DKIM, DMARC and MX records and get what to fix, with the values to publish
Mailtrap
Email API and SMTP for sending transactional and bulk emails, with email testing sandbox for safe development
PostStack
EU-hosted email API for transactional and marketing email, with contacts, broadcasts, and analytics
RankFabrik Verify
Validate email addresses for deliverability, syntax and disposable detection
Sendgrid
A cloud-based SMTP provider that allows you to send emails without having to maintain email servers
Sendinblue
A service that provides solutions relating to marketing and/or transactional email and/or SMS
SendRaven
Email for AI agents: send email, receive replies as threads, with per-key send limits and approvals
SMTPfast
Send transactional email, manage contacts and broadcasts, free 3,000 emails/month
TempMailGrab
Disposable inboxes for email testing with OTP extraction and webhooks
uchecker
Bulk email verification with full SMTP server responses
Xeramail Temp Mail
Temp email address REST API for privacy, testing, automation with OTP extraction