--- title: Transactional Emails description: Send emails via API icon: Send --- Transactional emails are emails sent directly through the API. They are typically used for one-to-one communication, such as password resets, order confirmations, and notifications. ## Sending with attachments Plunk supports sending attachments with transactional emails. By default, you can include up to 10 attachments per email with a maximum total size of 10MB. Attachments should be base64 encoded and included in the `attachments` array when sending the email via the [/v1/email/send](/api-reference/public-api/sendEmail) endpoint. The total message size cannot exceed 40 MB. Self-hosters can adjust the defaults — see [Environment variables](/self-hosting/environment-variables). ## Sending from a template You can also send transactional emails using a [template](/concepts/templates) you have created in the dashboard. This allows you to reuse the same design and content for multiple emails, while still personalizing them with contact data. ## What's next Full reference for `POST /v1/send`. Author reusable email designs. Authenticating requests with `sk_*` and `pk_*` keys. Track delivery, opens, clicks, and bounces of your sends.