How do I send an email with Python?

Make one authenticated HTTP POST to an email API with the requests library: from, to, subject, and html in a JSON body, a bearer token in the header. You get a message ID back and delivery events on your webhook. No smtplib, no SMTP server, no app passwords.

Should I use smtplib or an email API?

Use smtplib for a personal script on your own machine. Use an email API for anything a product depends on: it removes SMTP connection management, survives provider auth changes, and adds deliverability, tracking, and delivery events.

Can Python send email through Gmail?

Yes, with an app password over SMTP, but app passwords expire, security alerts fire, and the daily cap is built for a person. For production email, send through a platform and keep Gmail as your mailbox.

Send Email with Python: One POST, No SMTP

The smtplib way, and what it costs you

Every Python email tutorial starts the same way: import smtplib, connect to smtp.gmail.com, pick port 587 or 465, generate an app password, build a MIME message. It works, on your machine, today.

Then the app password expires. Or port 25 is blocked on the server. Or Gmail's daily cap hits, because that cap was built for a person, not a product. smtplib sends mail; it does nothing for deliverability, tracking, or what happens after the send.

One POST, and the send is handled

PythonPOST /v1/my/messages

import requests

requests.post(
  "https://api.nitrosend.com/v1/my/messages",
  headers={"Authorization": "Bearer $NITROSEND_API_KEY"},
  json={
    "from": "[email protected]",
    "to": "[email protected]",
    "subject": "Welcome",
    "html": "<p>You're in.</p>",
  },
)

That is the whole integration. The requests library you already have, a bearer token from the environment, and a JSON body. SPF, DKIM, and DMARC are handled on the platform side, which is the part that decides whether your email lands in the inbox.

And before anything ships, run my preflight. Resolve every wrapped CTA URL, check the spam score, weigh images against text, lint for dark mode, and send a test to a seed address. Some platforms build this in. If yours doesn't, do it yourself, every time.

The API also takes a dry_run flag: pass it and the call validates recipients and configuration without sending anything, which is exactly what you want in a test suite. Treat it as a check on the request, not a guarantee about delivery. I've watched a dry run validate cleanly and the real send still fail on something the environment only reveals live, which is why the seed-address test stays in my preflight no matter what the validator says.

Full parameters, responses, and error codes live in the REST API docs and the API reference.

Python Node.js PHP Go Rust +5

send.py requests · stdlib-adjacent

import requests

requests.post(
  "https://api.nitrosend.com/v1/messages",
  headers={"Authorization": f"Bearer {KEY}"},
  json={"to": to, "subject": subj,
        "html": body})

202 ACCEPTED

{ "id": "msg_9f2c",
  "status": "accepted" }

And the part no library gives you

The same account exposes an MCP server, so the agent writing your code can also run your email. Point Claude, Cursor, or Codex at api.nitrosend.com/mcp and it composes, previews, and stages sends, with a human approving every one. The API is for your code. The MCP is for your agent. One platform either way.

Every send comes back with a message ID, and delivery events follow on your webhook: delivered, opened, bounced. No dashboard required to know what happened. If you are staying on SMTP, how to set up SMTP is the setup to follow, and SPF, DKIM and DMARC authentication is what stops those sends landing in spam.

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Send email with Python

The smtplib way, and what it costs you

One POST, and the send is handled

And the part no library gives you

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