The API-first SMTP sandbox for high-scale engineering. Generate isolated inboxes in milliseconds, verify emails via REST API, and integrate seamlessly with your CI/CD pipelines.
Bridging the gap between automated unit tests and manual QA. Developers integrate via REST API to ensure delivery logic works, while QA teams verify render fidelity, forwarders, and content logic visually through our real-time dashboard.
Test your email flows like you test your code. DevInbox provides a thread-safe, isolated SMTP environment for every test run, ensuring zero flaky tests due to shared state.
Each createInbox() generates a unique
email and SMTP credential set. No cross-contamination.
We handle the SMTP infrastructure. You just grab
the username and password from the response.
Verify content using Mustache syntax or Regex. Extract magic links and OTPs instantly.
Native SDKs & Integrations:
// npm install @dev-inbox/client-api import { MailboxesApi, MessagesApi } from '@dev-inbox/client-api'; // 1. Create isolated inbox const inbox = await mailboxesApi.createMailbox(); // 2. Trigger auth flow with unique email await page.fill('#email', inbox.data.key + '@devinbox.io'); // 3. Verify OTP instantly via API const msg = await messagesApi.getLastMessage(inbox.data.key);
# 1. Generate ephemeral SMTP credentials inbox = client.create_inbox() # 2. Inject into app & send verification app.config.smtp = inbox.smtp_credentials app.send_verification(inbox.email) # 3. Assert content matches template msg = inbox.wait_for(subject="Verify") assert "Welcome" in msg.html
# 1. Create inbox via REST API curl -X POST https://api.devinbox.io/inboxes # 2. Response includes unique SMTP creds { "email": "test_8f92@devinbox.io", "smtp_user": "user_8f92", "smtp_pass": "sec_99a8d..." }
Automate your React Native and Flutter email authentication flows. Generate test accounts on the device, perform actions, and verify emails without ever leaving the test runner.
// npm install @dev-inbox/client-api import { MailboxesApi, MessagesApi } from '@dev-inbox/client-api'; // Create inbox for mobile testing const inbox = await mailboxesApi.createMailbox(); // Fill Native Input await element(by.id('email_input')).typeText(inbox.data.key + '@devinbox.io'); // Wait for email & verify via API const msg = await messagesApi.getLastMessage(inbox.data.key);
// Flutter Integration Test final inbox = await DevInbox.create(); await tester.enterText(find.byType(TextField), inbox.email); await tester.tap(find.text('Sign Up')); // Verify Email Arrival final email = await inbox.waitForEmail(subject: 'Welcome'); expect(email.body, contains('Verification Code'));
Sign up to get started
DevInbox provides a REST API that allows you to create disposable email addresses programmatically. You can then trigger your system to send emails to these addresses and verify the content, recipients, and timing through our API. This makes it easy to automate email testing in your CI/CD pipeline.
Absolutely! DevInbox integrates seamlessly with Playwright, Selenium, Cypress, and other testing frameworks. You can generate unique email addresses for each test run, ensuring test isolation and preventing conflicts between parallel test executions.
Email retention varies by plan: Developer (1 hour), Team (24 hours), Business (7 days), and Enterprise (15 days). This ensures you have enough time to verify your tests while keeping storage costs manageable. All emails are automatically purged after the retention period.
Yes, absolutely. All emails are encrypted in transit and at rest. We never share your data with third parties. Each inbox is completely isolated, and emails are automatically deleted after the retention period for your plan.
Yes! All paid plans include custom domain support. Simply add your domain, configure the required DNS records (MX, SPF, DKIM), and start generating email addresses like test@yourdomain.com. This is perfect for staging environments and realistic testing scenarios.
DevInbox is built specifically for CI/CD automation with sub-second inbox creation, thread-safe isolation, and comprehensive API access. Unlike traditional email testing tools, we provide real SMTP credentials, webhook support, and are designed for high-scale parallel test execution.
Absolutely! DevInbox works great with React Native, Flutter, and native iOS/Android testing frameworks. Generate test email addresses programmatically, trigger authentication flows in your app, then verify email delivery through our API - all without leaving your test environment.
Yes, you can upgrade or downgrade your plan at any time. Upgrades take effect immediately with prorated billing. When downgrading, the change takes effect at your next billing cycle, so you keep your current plan's benefits until then. The free Developer plan has no time limits.
Start for free, scale with your test suite. Up to 10x cheaper than competitors—no hidden fees, no surprises.
For individual hacking.
Get StartedFor small collaborative teams.
Sign UpScalable volume for growing businesses.
Get StartedDedicated capacity & support.
Contact Sales1) Any email received, forwarded, or webhook triggered is counted as a single operation by the SMTP Server.
2) Any call to the API server (for example the verification of the last message received) counts as a single operation.
*Rate limiting applies to all plans.