Configure Email Sending

Note

All three methods can be configured simultaneously. When sending emails, it will prioritize using resend, if resend is not configured, it will use smtp.

If a Cloudflare authenticated forwarding email address is configured, CF's internal API will be prioritized for sending emails

Send Emails Using Resend

Register at https://resend.com/domains and add DNS records according to the instructions.

Create an api key on the API KEYS page.

Then execute the following command to add RESEND_TOKEN to secrets:

NOTE

If you find this troublesome, you can also put it directly in plain text under [vars] in wrangler.toml, but this is not recommended

If you deployed through the UI, you can add it under Variables and Secrets in the Cloudflare UI interface.

# Switch to worker directory
cd worker
wrangler secret put RESEND_TOKEN

If you have multiple domains with different api keys, you can add multiple secrets in wrangler.toml, named RESEND_TOKEN_ + <UPPERCASE DOMAIN WITH . REPLACED BY _>, for example:

wrangler secret put RESEND_TOKEN_XXX_COM
wrangler secret put RESEND_TOKEN_DREAMHUNTER2333_XYZ

Send Emails Using SMTP

The format of SMTP_CONFIG is as follows, where key is the domain name and value is the SMTP configuration. For SMTP configuration format details, refer to zou-yu/worker-mailer

{
    "awsl.uk": {
        "host": "smtp.xxx.com",
        "port": 465,
        "secure": true,
        "authType": [
            "plain",
            "login"
        ],
        "credentials": {
            "username": "username",
            "password": "password"
        }
    }
}

Then execute the following command to add SMTP_CONFIG to secrets:

NOTE

If you find this troublesome, you can also put it directly in plain text under [vars] in wrangler.toml, but this is not recommended

If you deployed through the UI, you can add it under Variables and Secrets in the Cloudflare UI interface.

# Switch to worker directory
cd worker
wrangler secret put SMTP_CONFIG

Send Emails to Authenticated Forwarding Addresses on Cloudflare

Only supported for CLI deployment, add send_email configuration in wrangler.toml.

The destination email address must be an authenticated email address on Cloudflare, which has significant limitations. If you need to send emails to other addresses, you can use resend or smtp to send emails.

# Send emails through Cloudflare
send_email = [
   { name = "SEND_MAIL" },
]

Admin console account configuration Verified address list (can send emails through CF internal API)