Catch every email,
every time.
Your developer-first fake inbox for testing emails, SMS, voice IVR, push notifications, and webhook dumps.
.env
SMTP & REST
# 1. Point your app to Sinkbox
MAIL_HOST=smtp.sinkbox.dev
MAIL_USERNAME=api_user
MAIL_PASSWORD=api_password
# 2. Inspect with instant simulator previews
✓ Email HTML linting & spam scoring
✓ SMS, Push, Voice IVR & Webhooks
Welcome back
Sign in with your passkey, or with a magic link.
or magic link
Don't have an account? Sign up for free