Resend Python SDK

Installation

To install Resend Python SDK, simply execute the following command in a terminal:

pip install resend

Setup

First, you need to get an API key, which is available in the Resend Dashboard.

import resend
import os

resend.api_key = "re_yourkey"

Example

You can get an overview about all parameters in the Send Email API reference.

import os
import resend

resend.api_key = "re_yourkey"

params: resend.Emails.SendParams = {
    "from": "onboarding@resend.dev",
    "to": ["delivered@resend.dev"],
    "subject": "hi",
    "html": "<strong>hello, world!</strong>",
    "reply_to": "to@gmail.com",
    "bcc": "bcc@resend.dev",
    "cc": ["cc@resend.dev"],
    "tags": [
        {"name": "tag1", "value": "tagvalue1"},
        {"name": "tag2", "value": "tagvalue2"},
    ],
}

email: resend.Emails.SendResponse = resend.Emails.send(params)
print(email)

Async Support

The SDK supports async operations via httpx. Install the async extra:

pip install resend[async]

Once installed, async methods (suffixed with _async) work automatically — no extra setup needed:

import asyncio
import resend

resend.api_key = "re_yourkey"

async def main():
    params: resend.Emails.SendParams = {
        "from": "onboarding@resend.dev",
        "to": ["delivered@resend.dev"],
        "subject": "hi",
        "html": "<strong>hello, world!</strong>",
    }

    email: resend.Emails.SendResponse = await resend.Emails.send_async(params)
    print(email)

if __name__ == "__main__":
    asyncio.run(main())

Custom async client

To use a custom async HTTP client or configure options like timeouts, set resend.default_async_http_client:

import resend

resend.api_key = "re_yourkey"
resend.default_async_http_client = resend.HTTPXClient(timeout=60)

Legacy configurations that assign an AsyncHTTPClient to resend.default_http_client are also supported. Async requests select a client in this order:

1. A replacement client assigned to resend.default_async_http_client.
2. An AsyncHTTPClient assigned to resend.default_http_client.
3. The automatic HTTPXClient, if httpx is installed.

Setting resend.default_async_http_client = None still permits the legacy fallback. Prefer the dedicated async setting for new code, so the sync client remains available for synchronous calls.