Email APIs let you send transactional emails, verify addresses, and manage mailing lists. Handle email delivery, validation, and inbox management without running your own mail servers.
Last verified: November 12, 2026
| Name | Description | Auth | HTTPS | CORS | Uptime (30 days) |
|---|---|---|---|---|---|
| Academic Email API | This API allows you to verify whether an email belongs to a recognized educational institution | apikey | Yes | yes | 100% (5 checks) |
| anon.li | Create and manage anonymous email aliases, forwarding recipients and custom domains | apikey | Yes | no | 100% (4 checks) |
| Atomic Mail | Email for AI agents: programmatic inbox creation and send/receive over JMAP | apikey | Yes | unknown | 100% (5 checks) |
| Autentify Verify | Brazilian email verification: deliverable, undeliverable, risky or unknown, with the reason | apikey | Yes | no | 100% (2 checks) |
| B2B Email & Domain Scorer | Email verification: MX, disposable/free/role detection, typo fix and a keep/fix/drop action | apikey | Yes | unknown | 100% (5 checks) |
| Best Temp Mail | Disposable inboxes for automated email testing, with OTP extraction | none | Yes | no | 100% (5 checks) |
| Brevo (formerly Sendinblue) | A service that provides solutions relating to marketing and/or transactional email and/or SMS | apikey | Yes | unknown | 80.0% (5 checks) |
| Cloudmersive Validate | Validate email addresses, phone numbers, VAT numbers and domain names | apikey | Yes | yes | 100% (5 checks) |
| Disban | Classify email domains as disposable, free, alias, testing or parked to block fake signups | apikey | Yes | no | 100% (5 checks) |
| DropMail | GraphQL API for creating and managing ephemeral e-mail inboxes | none | Yes | unknown | 100% (5 checks) |
| Email Spam Tester | Send a test message and get a spam score, 41 checks with RFC citations and a fix plan | none | Yes | yes | 100% (5 checks) |
| Email Validation | Validate email addresses for deliverability and spam | apikey | Yes | yes | 100% (5 checks) |
| email59 | Email API for apps and agents: send from a ready @email59.com address with no DNS setup, plus email verification codes, address checks and campaigns | apikey | Yes | no | 100% (5 checks) |
| EmailJS | Send emails directly from client-side JavaScript without a backend server | apikey | Yes | yes | 100% (5 checks) |
| Guerrilla Mail | Disposable temporary Email addresses | none | Yes | unknown | 100% (5 checks) |
| Hail | Add AI calls, SMS, and email to apps and AI agents through one API | apikey | Yes | no | 100% (5 checks) |
| Heybounce | Email Verification API | none | Yes | yes | 100% (5 checks) |
| ImprovMX | API for free email forwarding service | apikey | Yes | unknown | 100% (5 checks) |
| inboxsink | Disposable inboxes for end-to-end tests that wait for the email and extract OTP codes | apikey | Yes | no | 100% (5 checks) |
| IndiePitcher | Everything email for your startup with markdown support | apikey | Yes | yes | 100% (5 checks) |
| Kickbox | Email verification API | none | Yes | yes | 100% (5 checks) |
| Kiprio Email Validate | Free email validation: MX check, disposable detection, syntax | apikey | Yes | yes | 100% (5 checks) |
| mail.gw | 10 Minute Mail | none | Yes | yes | 100% (5 checks) |
| mail.tm | Temporary Email Service | none | Yes | yes | 100% (5 checks) |
| mailboxlayer | Email address validation | apikey | Yes | unknown | 100% (5 checks) |
| MailboxValidator | Validate email address to improve deliverability | apikey | Yes | unknown | 100% (5 checks) |
| MailChannels | Send transactional email over HTTPS with official JavaScript, Python and PHP SDKs | apikey | Yes | no | 100% (5 checks) |
| MailCheck.ai | Prevent users to sign up with temporary email addresses | none | Yes | unknown | 100% (5 checks) |
| mailfloss | Stop spam signups: block disposable and invalid emails and suggest typo fixes. 500 free a month | apikey | Yes | yes | 100% (5 checks) |
| Mailfornet | Disposable inboxes for end-to-end signup tests, with long-polling and HMAC-signed webhooks | apikey | Yes | yes | 100% (5 checks) |
| MailRambo | Verify email deliverability with a strict yes/no, disposable and catch-all detection | apikey | Yes | no | 100% (5 checks) |
| MailSenpai DNS Check | Check a domain's SPF, DKIM, DMARC and MX records and get what to fix, with the values to publish | none | Yes | yes | 100% (5 checks) |
| Mailtrap | A service for the safe testing of emails sent from the development and staging environments | apikey | Yes | unknown | 80.0% (5 checks) |
| MailValid | Real-time email verification API with SMTP, MX, disposable, role-based, and catch-all detection. Verify single or bulk emails with confidence scoring | apikey | Yes | yes | 100% (5 checks) |
| MailVeri | Email verification API: SMTP, catch-all, disposable and role detection for single and bulk checks | apikey | Yes | yes | 100% (4 checks) |
| Nitrosend | Send marketing and transactional email; manage contacts, segments and flows | apikey | Yes | no | 100% (5 checks) |
| NoParam | Email validation API for real-time & bulk checking | apikey | Yes | unknown | 100% (5 checks) |
| Notilify | A seamless messaging platform & API to send all types of SMS | apikey | Yes | yes | 100% (5 checks) |
| PostStack | EU-hosted email API for transactional and marketing email, with contacts, broadcasts, and analytics | apikey | Yes | no | 100% (5 checks) |
| Proweblook Email Checker | Validate email addresses without sending | apikey | Yes | yes | 100% (5 checks) |
| RankFabrik Verify | Validate email addresses for deliverability, syntax and disposable detection | apikey | Yes | unknown | 100% (5 checks) |
| Resend | Email API for developers | apikey | Yes | yes | 100% (5 checks) |
| Sendgrid | A cloud-based SMTP provider that allows you to send emails without having to maintain email servers | apikey | Yes | unknown | 100% (5 checks) |
| Sendinblue | A service that provides solutions relating to marketing and/or transactional email and/or SMS | apikey | Yes | unknown | 100% (4 checks) |
| SendRaven | Email for AI agents: send email, receive replies as threads, with per-key send limits and approvals | apikey | Yes | no | 100% (5 checks) |
| SMTP Senpai | EU-hosted transactional email API and SMTP relay: DKIM on your domain, signed webhooks, delivery events | apikey | Yes | no | 100% (5 checks) |
| SMTPfast | Send transactional email, manage contacts and broadcasts, free 3,000 emails/month | apikey | Yes | yes | 100% (5 checks) |
| StopMailing | Temporary email addresses with a free, no-signup REST API: create, read messages, live updates (SSE) | none | Yes | yes | 100% (5 checks) |
| Sweego | Self-serve multichannel notification platform for transactional email, SMS, push web& mobile, chat, in-app | apikey | Yes | yes | 100% (5 checks) |
| Sweep Emails | Reliable email validation API with Free tier | apikey | Yes | no | 100% (5 checks) |
| TempMailGrab | Disposable inboxes for email testing with OTP extraction and webhooks | apikey | Yes | no | 100% (5 checks) |
| Temporary and Disposable emails API | This API provides temporary & disposable email addresses | apikey | Yes | yes | 100% (5 checks) |
| Trueguard | Trueguard offers API for detecting temporary emails, free-tier abusers and automated bots | apikey | Yes | no | 100% (5 checks) |
| TrustLookup | Verify email syntax, MX and live mailbox; detect disposable, role and catch-all addresses | apikey | Yes | no | 100% (1 check) |
| uchecker | Bulk email verification with full SMTP server responses | apikey | Yes | unknown | 100% (5 checks) |
| Vetto | Check email domains in bulk for disposable providers and dead domains, no key needed | none | Yes | yes | 100% (5 checks) |
| Xeramail Temp Mail | Temp email address REST API for privacy, testing, automation with OTP extraction | apikey | Yes | no | 100% (5 checks) |
| Zyntra | Unlimited e-mail inboxes with API access. Catch OTPs, reset links, and sign-up emails in test flows | apikey | Yes | unknown | 100% (5 checks) |
12 of these APIs require no authentication — you can start making requests immediately without signing up for an account. Just pick one from the table above, check its documentation, and send your first request.
46 APIs in this category require a free API key. This usually means creating a free account on the provider's website and copying your key from the dashboard. The process typically takes less than a minute.
Not sure where to start? Check the uptime column: it shows how often each API's documentation responded to our daily checks over the last 30 days, and the dot shows whether it responded at the latest check. For browser-based projects, check that the API supports CORS.
Yes, all APIs listed on API Bouncer have a free tier. Some are completely open (no sign-up needed), while others require a free account to get an API key. Free tiers typically have rate limits — check each API's documentation for specifics.
It depends on your needs. Consider: Do you need authentication or prefer no-auth? Does your project need CORS support for browser access? How many requests will you make? Start with a no-auth API to prototype quickly, then switch to a more feature-rich option if needed.
We run periodic health checks on all listed APIs. The "Status" column shows whether each API was responding at our last check. APIs marked as "alive" were recently verified. You can also test any API yourself using curl or our guides on testing APIs.
Most free APIs allow commercial use, but terms vary by provider. Always check the specific API's terms of service. Some APIs have separate free and commercial tiers with different rate limits.
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