Overview

Send transactional and bulk emails through Mailtrap's reliable infrastructure

Mailtrap's Email API provides a powerful and reliable way to send transactional and bulk emails through our infrastructure. Whether you're sending order confirmations, password resets, or marketing campaigns, our API has you covered.

Getting Started

Verify Your Sending Domain

Before sending emails, you need to verify ownership of your sending domain:

Go to Sending Domains
Add your domain
Configure DNS records (SPF, DKIM, DMARC)
Verify the records

Emails sent from unverified domains will be rejected.

Get Your API Key

Navigate to API Tokens in your Mailtrap account and generate a new API token with sending permissions.

Keep your API token secure and never expose it in client-side code.

Install SDK or Use API

Choose an SDK for your programming language or use the API directly with cURL:

No installation required. Use cURL or any HTTP client to make API requests directly.

Add GitHub Packages source to nuget.config:

<packageSources>
  <add key="github" value="https://nuget.pkg.github.com/railsware/index.json" />
</packageSources>

Then install:

dotnet add package Mailtrap

Send Your First Email

Here's a minimal example to send your first email:

curl -X POST https://send.api.mailtrap.io/api/send \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "from": {"email": "[email protected]"},
    "to": [{"email": "[email protected]"}],
    "subject": "Hello from Mailtrap",
    "text": "Welcome to Mailtrap Email API!"
  }'

import { MailtrapClient } from "mailtrap";

const client = new MailtrapClient({
  token: process.env.MAILTRAP_API_KEY
});

await client.send({
  from: { email: "[email protected]" },
  to: [{ email: "[email protected]" }],
  subject: "Hello from Mailtrap",
  text: "Welcome to Mailtrap Email API!"
});

use Mailtrap\MailtrapClient;
use Mailtrap\Mime\MailtrapEmail;
use Symfony\Component\Mime\Address;

$mailtrap = MailtrapClient::initSendingEmails(
    apiKey: $_ENV['MAILTRAP_API_KEY']
);

$email = (new MailtrapEmail())
    ->from(new Address('[email protected]'))
    ->to(new Address('[email protected]'))
    ->subject('Hello from Mailtrap')
    ->text('Welcome to Mailtrap Email API!');

$mailtrap->send($email);

import mailtrap as mt

client = mt.MailtrapClient(token="YOUR_API_KEY")

mail = mt.Mail(
    sender=mt.Address(email="[email protected]"),
    to=[mt.Address(email="[email protected]")],
    subject="Hello from Mailtrap",
    text="Welcome to Mailtrap Email API!"
)

client.send(mail)

require 'mailtrap'

client = Mailtrap::Client.new(api_key: 'YOUR_API_KEY')

mail = Mailtrap::Mail.from_content(
  from: { email: '[email protected]' },
  to: [{ email: '[email protected]' }],
  subject: 'Hello from Mailtrap',
  text: 'Welcome to Mailtrap Email API!'
)

client.send(mail)

using Mailtrap;
using Mailtrap.Emails.Models;
using Mailtrap.Emails.Requests;

using var mailtrapClientFactory = new MailtrapClientFactory("YOUR_API_KEY");
var client = mailtrapClientFactory.CreateClient();

var mail = new SendEmailRequest
{
      From = new EmailAddress("[email protected]"),
      To = new[] { new EmailAddress("[email protected]") },
      Subject = "Hello from Mailtrap",
      TextBody = "Welcome to Mailtrap Email API!"
};

await client.Email().Send(mail);

import io.mailtrap.api.sendingemails.SendingEmails;
import io.mailtrap.config.MailtrapConfig;
import io.mailtrap.factory.MailtrapClientFactory;
import io.mailtrap.model.request.emails.Address;
import io.mailtrap.model.request.emails.MailtrapMail;

var config = new MailtrapConfig.Builder()
    .token("YOUR_API_KEY")
    .build();

var client = MailtrapClientFactory.createMailtrapClient(config);

var mail = new MailtrapMail.Builder()
    .from(new Address("[email protected]"))
    .to(List.of(new Address("[email protected]")))
    .subject("Hello from Mailtrap")
    .text("Welcome to Mailtrap Email API!")
    .build();

client.sendingApi().emails().send(mail);

Email Sending Options

Transactional Emails

Best for real-time, one-to-one emails triggered by user actions:

Order confirmations
Password resets
Account notifications
System alerts
Welcome emails

Endpoint: https://send.api.mailtrap.io/api/send

Bulk Stream

Optimized for high-volume marketing campaigns:

Newsletters
Promotional campaigns
Product announcements
Marketing emails

Endpoint: https://bulk.api.mailtrap.io/api/send

Learn more about Bulk Stream and when to use it for your marketing emails.

Batch Sending

Send up to 500 emails in a single API call:

Personalized notifications
Event invitations
Account updates
Targeted campaigns

Endpoint: https://send.api.mailtrap.io/api/batch or https://bulk.api.mailtrap.io/api/batch

Use send.api.mailtrap.io for transactional batch emails or bulk.api.mailtrap.io for marketing batch emails, depending on your stream.

Limits: 500 messages per call, 50 MB total payload

Features

Email Templates

Create reusable templates with variables for consistent branding and easy updates.

Manage Templates

Analytics & Tracking

Monitor delivery rates, opens, clicks, and bounces in real-time.

View Analytics

Webhooks

Receive real-time notifications for email events like delivery, bounce, and opens.

Configure Webhooks

Testing with Sandbox

Before going to production, test your email integration with our Sandbox. All official SDKs support Sandbox mode with an easy switch.

We recommend using environment variables to manage the switch between Sandbox and Production modes.

import { MailtrapClient } from "mailtrap";

// Switch to sandbox mode for testing
const client = new MailtrapClient({
  token: process.env.MAILTRAP_API_KEY,
  sandbox: true,
  testInboxId: 123456 // Your test inbox ID
});

await client.send({
  from: { email: "[email protected]" },
  to: [{ email: "[email protected]" }],
  subject: "Test Email",
  text: "This email will be captured in your Sandbox inbox."
});

use Mailtrap\MailtrapClient;
use Mailtrap\Mime\MailtrapEmail;
use Symfony\Component\Mime\Address;

// Switch to sandbox mode for testing
$mailtrap = MailtrapClient::initSendingEmails(
    apiKey: $_ENV['MAILTRAP_API_KEY'],
    isSandbox: true,
    inboxId: 123456 // Your test inbox ID
);

$email = (new MailtrapEmail())
    ->from(new Address('[email protected]'))
    ->to(new Address('[email protected]'))
    ->subject('Test Email')
    ->text('This email will be captured in your Sandbox inbox.');

$mailtrap->send($email);

import mailtrap as mt

# Switch to sandbox mode for testing
client = mt.MailtrapClient(
    token="YOUR_API_KEY",
    sandbox=True,
    test_inbox_id=123456  # Your test inbox ID
)

mail = mt.Mail(
    sender=mt.Address(email="[email protected]"),
    to=[mt.Address(email="[email protected]")],
    subject="Test Email",
    text="This email will be captured in your Sandbox inbox."
)

client.send(mail)

require 'mailtrap'

# Switch to sandbox mode for testing
client = Mailtrap::Client.new(
  api_key: 'YOUR_API_KEY',
  sandbox: true,
  inbox_id: 123456 # Your test inbox ID
)

mail = Mailtrap::Mail.from_content(
  from: { email: '[email protected]' },
  to: [{ email: '[email protected]' }],
  subject: 'Test Email',
  text: 'This email will be captured in your Sandbox inbox.'
)

client.send(mail)

using Mailtrap;
using Mailtrap.Emails.Models;
using Mailtrap.Emails.Requests;

using var mailtrapClientFactory = new MailtrapClientFactory("<API-TOKEN>");
        var mailtrapClient = mailtrapClientFactory.CreateClient();
        var mail = new SendEmailRequest
        {
            From = new EmailAddress("[email protected]"),
            To = new[] { new EmailAddress("[email protected]") },
            Subject = "Hello from Mailtrap",
            TextBody = "Welcome to Mailtrap Email API!"
        };
        await mailtrapClient
            .Test(123456) // Sandbox ID
            .Send(mail);

import io.mailtrap.config.MailtrapConfig;
import io.mailtrap.factory.MailtrapClientFactory;
import io.mailtrap.model.request.emails.Address;
import io.mailtrap.model.request.emails.MailtrapMail;

// Switch to sandbox mode for testing
var config = new MailtrapConfig.Builder()
    .token("YOUR_API_KEY")
    .sandbox(true)
    .testInboxId(123456L) // Your test inbox ID
    .build();

var client = MailtrapClientFactory.createMailtrapClient(config);

var mail = new MailtrapMail.Builder()
    .from(new Address("[email protected]"))
    .to(List.of(new Address("[email protected]")))
    .subject("Test Email")
    .text("This email will be captured in your Sandbox inbox.")
    .build();

client.sendingApi().emails().send(mail);

Sandbox emails are captured in your test inbox instead of being delivered to recipients. Find your test inbox ID in your Mailtrap Sandbox.

PreviousOpenAPI Specs NextSend Email - Transactional

Last updated 8 days ago

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Getting Started

Verify Your Sending Domain

Get Your API Key

Install SDK or Use API

Send Your First Email

Email Sending Options

Transactional Emails

Bulk Stream

Batch Sending

Features

Email Templates

Analytics & Tracking

Webhooks

Testing with Sandbox