Mailchk

Email Testing API

Run your email testing on autopilot

Create disposable inboxes, capture every email your app sends, and assert on content — all inside your existing test suite.

Use Cases

Automate processes you never thought you could

If your app sends email, you can now test it automatically.

End-to-End Test Automation

Write Playwright, Cypress, or Selenium tests that sign up with a test inbox address, then verify the welcome email arrived with the correct content and links.

Playwright / Cypress / Selenium

OTP & Magic Link Verification

Create an inbox, trigger a login flow, and read the auto-extracted OTP from detail.codes — no regex required. Magic links are validated automatically too.

Auth Flow Testing

CI/CD Email Verification

Add email assertions to your GitHub Actions, GitLab CI, or Jenkins pipeline. Every push verifies that your transactional emails still work.

GitHub Actions / GitLab CI

Template QA Before Deploy

Render your email templates with real data into a test inbox. Catch broken layouts, missing variables, and styling regressions before they reach customers.

Pre-Deploy Checks

Transactional Email Monitoring

Verify that password resets, order confirmations, and welcome emails contain the right data, render correctly, and include all expected attachments.

Content Verification

Email Deliverability Debugging

Inspect SPF, DKIM, and DMARC headers on captured emails. Catch authentication failures and routing issues before they tank your sender reputation.

Header Analysis

Live Preview

Watch an email test run

Create an inbox, trigger your email, and assert on the content — all automated.

npx playwright test signup.spec.ts

Running 1 test using 1 worker

test('signup sends welcome email')

Compatibility

Made to fit into your existing stack

Pure REST API with no SDK required. Works with every test framework, CI system, and email sender.

PlaywrightCypressSeleniumJestpytestPHPUnitGitHub ActionsGitLab CIJenkinsCircleCISendGridPostmarkAmazon SESMailgunResend

Virtual SMTP Server

Capture every email safely

Mailchk acts as a virtual SMTP endpoint. Emails sent to your test addresses are captured instantly — they never reach real customers, and you can inspect every detail.

1

Point your app at a test address

Create a test inbox via API or dashboard. You get a unique address like test-k9m2x@mailchk.email. Use it anywhere you'd normally put a recipient email.

2

Send via any provider or SMTP

SendGrid, Postmark, Amazon SES, Mailgun, raw SMTP, or your own mail server — it doesn't matter. If it can send an email, our virtual server catches it. No SMTP credentials to configure, no DNS changes.

3

Emails are captured, never delivered

The mailchk.email domain is a catch-all backed by our mail infrastructure. No email ever leaves our servers — zero risk of accidentally emailing real customers during testing.

4

Inspect the full email via API

Retrieve the captured email within seconds. Get rendered HTML, plain text, every header (SPF, DKIM, DMARC results), and all attachments as base64. Assert on anything.

Your Application

Triggers email (signup, reset, receipt, etc.)

→ sends to test-k9m2x@mailchk.email

Your Email Service

SendGrid, SES, Postmark, Mailgun, SMTP...

→ delivers via MX to mailchk.email

Mailchk Virtual SMTP

Catches & stores the email. Parses HTML, text, headers, attachments.

→ GET /v1/test-inboxes/:id/messages

Your Test Suite

Retrieves email, asserts on subject, body, headers, attachments

No SMTP credentials to manage

Unlike other providers, with Mailchk you don't need to configure SMTP credentials or change your app's mail transport. Just send to the test address — our domain's MX records handle the rest.

Features

Go beyond basic email testing

Auto OTP & Code Extraction

OTPs, verification codes, PINs, and magic codes are automatically extracted from every email. No regex needed — just read the codes array from the API response.

Link Validation

Every link in the email is automatically checked for a valid HTTP response. Catch broken links, expired tokens, and dead URLs before your users do.

API-First Design

Every operation available via REST API. Create inboxes, poll for messages, and inspect emails programmatically. Built for automation from day one.

Full Email Parsing

Get the complete picture — rendered HTML, plain text fallback, every header, and attachment metadata (name, type, size). Nothing hidden.

Works With Any Sender

SendGrid, Postmark, Amazon SES, Mailgun, or raw SMTP — if it can send email, we can catch it. Zero configuration on your end.

Header Deep-Dive

SPF, DKIM, DMARC authentication results. Routing headers. Custom X-headers your app adds. Debug deliverability issues before they happen.

Stop shipping broken emails

Add email assertions to your test suite in under 5 minutes. Create an inbox, send your email, verify it works. Every deploy.

FAQ

Common Questions