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Plunk

Send via SMTP
or API. Your call.

Point any existing client or framework at Plunk. Same domains, same tracking, same price.

Start for freeSMTP docs
smtpTLS
hostsmtp.useplunk.com
port587
usernameplunk
passwordsk_your_secret_key

What you get

The protocol is the only old thing about it.

  • Credentials, not a rewrite

    Swap the host, port and credentials in whatever already sends your mail. Nothing else about your application changes.

    smtp.useplunk.com : 587

  • TLS on 465 and 587

    Encrypted in transit on both the implicit and STARTTLS ports.

  • Any client, any language

    Outlook, Thunderbird, Apple Mail, or any framework with an SMTP transport. There is no SDK to adopt.

  • The same pipeline as the API

    SMTP mail goes out over the same infrastructure, against the same verified domains, with the same open and click tracking.

  • Attachments and custom headers

    Full MIME support, multiple recipients, and your own headers passed straight through.

SMTP or API

Both send through the same pipeline. These are the differences.

comparison
FeatureSMTPAPI
ProtocolSMTPHTTP / REST
SetupCredentialsAPI key
Works with mail clientsYesNo
Open and click trackingYesYes
AttachmentsYesYes
Plunk templatesNoYes
Triggers workflowsNoYes

When SMTP is the right answer

  • Legacy systems

    Something in your stack already speaks SMTP and nobody wants to touch it. Point it at Plunk and it keeps working, now with tracking.

    Zero code changes

  • Sending from a mail client

    People who live in Outlook or Apple Mail can send through your verified domain without learning an API.

    No technical knowledge needed

  • Frameworks without an HTTP client

    Older platforms, embedded systems and anything else where an SMTP transport is the only option available.

    Universal protocol support

Frequently asked questions

Should I use SMTP or the API?

Use SMTP when something already sends mail and you do not want to change it, or when a person is sending from a mail client. Use the API when you want Plunk templates or want the send to trigger a workflow.

Do SMTP sends get tracked?

Yes. SMTP mail goes out over the same infrastructure as API mail, so opens, clicks and bounces are recorded the same way.

Which ports and encryption are supported?

Port 587 with STARTTLS and port 465 with implicit TLS. Both are encrypted in transit.

Can I send from any address?

Only from domains you have verified on your project. Plunk checks the sending domain before accepting the message.

Point your app at Plunk.

Free plan: 1,000 emails a month. Paid: $0.001 an email.

Start for freeView pricing