Send16 Node.js SDK

The official Node.js SDK for the Send16 email platform. Built with TypeScript and works in Node.js, Deno, Bun, and edge runtimes.

Installation

npm install send16-mail
# or
pnpm add send16-mail
# or
yarn add send16-mail

Quick Start

import { Send16 } from 'send16-mail';

const send16 = new Send16('sk_live_xxxxx');

const { data, error } = await send16.emails.send({
  from: 'Acme <hello@acme.com>',
  to: ['user@gmail.com'],
  subject: 'Hello from Send16',
  html: '<p>Hello world</p>',
});

if (error) {
  console.error('Failed to send:', error.message);
} else {
  console.log('Email sent:', data.id);
}

Configuration

const send16 = new Send16('sk_live_xxxxx', {
  baseUrl: 'https://api.send16.com', // default
  timeout: 30000,                     // default: 30 seconds
});

Emails

Send a single email

const { data, error } = await send16.emails.send({
  from: 'Acme <hello@acme.com>',
  to: ['user@gmail.com'],
  subject: 'Hello',
  html: '<p>Hello world</p>',
});

Send with all options

const { data, error } = await send16.emails.send({
  from: 'Acme <hello@acme.com>',
  to: ['user@gmail.com'],
  cc: ['cc@example.com'],
  bcc: ['bcc@example.com'],
  replyTo: 'support@acme.com',
  subject: 'Invoice #1234',
  html: '<p>Please find your invoice attached.</p>',
  text: 'Please find your invoice attached.',
  headers: {
    'X-Custom-Header': 'value',
  },
  attachments: [
    {
      filename: 'invoice.pdf',
      content: '<base64-encoded-content>',
      contentType: 'application/pdf',
    },
  ],
  tags: [
    { name: 'category', value: 'invoices' },
  ],
  scheduledAt: '2026-04-01T09:00:00Z',
});

Batch send (up to 100 emails)

const { data, error } = await send16.emails.batch([
  {
    from: 'Acme <hello@acme.com>',
    to: ['alice@example.com'],
    subject: 'Hello Alice',
    html: '<p>Hi Alice!</p>',
  },
  {
    from: 'Acme <hello@acme.com>',
    to: ['bob@example.com'],
    subject: 'Hello Bob',
    html: '<p>Hi Bob!</p>',
  },
]);

Contacts

Create a contact

const { data, error } = await send16.contacts.create({
  email: 'user@test.com',
  firstName: 'John',
  lastName: 'Doe',
});

List contacts

const { data, error } = await send16.contacts.list();

// With pagination
const { data, error } = await send16.contacts.list({ page: 2, limit: 50 });

Get a contact

const { data, error } = await send16.contacts.get('contact-id');

Update a contact

const { data, error } = await send16.contacts.update('contact-id', {
  firstName: 'Jane',
  unsubscribed: false,
});

Delete a contact

const { data, error } = await send16.contacts.delete('contact-id');

Domains

List domains

const { data, error } = await send16.domains.list();

Get a domain

const { data, error } = await send16.domains.get('domain-id');

Verify a domain

const { data, error } = await send16.domains.verify('domain-id');

Error Handling

The SDK never throws on API errors. Every method returns { data, error }:

const { data, error } = await send16.emails.send({ ... });

if (error) {
  console.error(error.code);    // e.g. "HTTP_422", "TIMEOUT", "NETWORK_ERROR"
  console.error(error.message);  // Human-readable description
  return;
}

// data is guaranteed to be non-null here
console.log(data.id);

TypeScript

All types are exported for full type safety:

import type {
  SendEmailPayload,
  SendEmailResponse,
  Contact,
  Domain,
  ApiResponse,
  ApiError,
} from 'send16-mail';

License

MIT