Send your first email over SMTP

This quickstart shows you how to send a test email through the Emailit SMTP relay from your terminal, then connect your own app. Use SMTP when your software already has SMTP settings. For new code, the API does more.

Before you begin

• A verified sending domain. If you don’t have one yet, follow the first section of the API quickstart or Add a domain.
• An API key. Create one in Email API›API Keys with Add API key. Your API key is your SMTP password.

Your SMTP credentials

You can also see these settings on the SMTP Info card when you open a key in Email API›API Keys.

The relay offers TLS on every port but doesn’t force it. Always turn TLS on in your client so your API key isn’t sent in plain text.

Send a test email

Pick one of these tools. Replace hello@acme.com with an address on your verified domain, and ada@example.com with the email address you signed up with.

swaks

swaks is a command-line SMTP test tool. Install it with brew install swaks or apt install swaks, then run:

swaks --server smtp.emailit.com:587 --tls \
  --auth-user emailit --auth-password "$EMAILIT_API_KEY" \
  --from hello@acme.com --to ada@example.com \
  --header "Subject: Hello from Emailit SMTP" \
  --body "This is my first email sent through the Emailit SMTP relay."

swaks prints the whole SMTP conversation. The last reply from the server contains the email ID:

<~  250 2.0.0 OK: queued as em_2pX7cN4kQ9vLm3RtB8yWd1Zs

OpenSSL

OpenSSL is preinstalled on most systems and lets you type the SMTP commands yourself. First, encode your credentials for AUTH PLAIN:

printf '\0emailit\0%s' "$EMAILIT_API_KEY" | base64

Then open a connection and type the commands below, pasting the encoded string after AUTH PLAIN:

openssl s_client -connect smtp.emailit.com:587 -starttls smtp -crlf -quiet

EHLO localhost
AUTH PLAIN AGVtYWlsaXQAc2VjcmV0X...
MAIL FROM:<hello@acme.com>
RCPT TO:<ada@example.com>
DATA
From: Acme <hello@acme.com>
To: ada@example.com
Subject: Hello from Emailit SMTP

This is my first email sent through the Emailit SMTP relay.
.
QUIT

After AUTH PLAIN the server answers 235. After the line with a single ., it answers 250 2.0.0 OK: queued as em_….

Python

Python’s built-in smtplib needs no extra packages:

import os
import smtplib
from email.message import EmailMessage

msg = EmailMessage()
msg["From"] = "Acme <hello@acme.com>"
msg["To"] = "ada@example.com"
msg["Subject"] = "Hello from Emailit SMTP"
msg.set_content("This is my first email sent through the Emailit SMTP relay.")
msg.add_alternative("<p>This is my first email sent through the Emailit SMTP relay.</p>", subtype="html")

with smtplib.SMTP("smtp.emailit.com", 587) as smtp:
    smtp.starttls()
    smtp.login("emailit", os.environ["EMAILIT_API_KEY"])
    smtp.send_message(msg)

print("Accepted by Emailit")

If the script finishes without an exception, Emailit has accepted the email.

Check it in the dashboard

Go to Email API›Emails. Your email is at the top of the Outgoing tab, and its status changes from accepted to delivered once the recipient’s server accepts it. Each SMTP session also appears in Email API›Logs with the source SMTP, so you can see failed logins and rejected messages too.

Common replies

For every reply code, see SMTP troubleshooting.

Connect your app

Put the same settings into your app or framework. These guides show the exact configuration:

Next steps