Email API Service

Integrate transactional and marketing email directly into your product with a fast, reliable, and developer-friendly API.

From password resets and notifications to large-scale marketing campaigns, the API is designed to deliver emails quickly, reliably, and securely.

50ms
Avg. Response Time
99.99%
API Uptime SLA
10B+
Emails Sent via API
100+
Official SDKs
Send Emailsimg

Everything Developers Need to Send Email Reliably

Our email API is built for developers who need speed, flexibility, and reliability at scale.

Lightning-Fast Delivery

Engineered for performance with intelligent queuing and optimized infrastructure. Emails are processed and delivered quickly, so your application communications reach users without delay.

Learn More

Dynamic Templates

Create reusable templates using Handlebars or Liquid syntax with full variable support. Manage templates through the API or update them visually without touching your application code.

View Templates

Real-Time Webhooks

Receive instant notifications for key email events such as opens, clicks, bounces, and unsubscribes. Use these events to power automation workflows or trigger actions inside your product.

Explore Webhooks

Batch & Bulk Sending

Send large volumes of personalized emails through a single API request. The batch endpoint supports per-recipient variable substitution, enabling fully customized messages even at massive scale.

Batch Docs

Smart Retry Logic

Temporary delivery issues are handled automatically with intelligent retry mechanisms. Exponential backoff ensures messages are retried safely until successful delivery.

Learn More

Analytics & Tracking

Track campaign performance and message activity with detailed analytics. Access open rates, click data, deliverability insights, and per-message metrics directly through the API.

Explore Analytics

Attachments & Inline Images

Attach documents such as PDFs, invoices, and images to transactional emails. Inline image support ensures consistent rendering across email clients.

Learn More

Security & Auth

Protect your email infrastructure with API keys, OAuth 2.0 authentication, IP allowlisting, and scoped access tokens designed for secure multi-team environments.

Security Docs

Sub-Account Management

Manage multiple sending domains, clients, or projects from a single parent account. Perfect for SaaS platforms, agencies, and whitelabel products that need isolated sending environments.

Learn More

Go From Setup to Sending in Minutes

Our official SDKs and comprehensive developer documentation help you integrate email capabilities into your application quickly.

1

Install the SDK

Use a single command to install the SDK via package managers like npm, pip, composer, gem, or go get.

2

Authenticate with Your API Key

Create an API key in your dashboard and add it as an environment variable in your application.

3

Send Your First Email

Make a request to the /v1/emails/send endpoint with your email payload. Within milliseconds, the API processes your request and returns a delivery response.

4

Track & Improve Performance

Configure webhooks to receive real-time updates for opens, clicks, bounces, and other email events.

Node.js
Python
PHP
Ruby
Java
Installation & Setup
# Install via npm
npm install @truesend/node

# Set your API key
export TRUESEND_API_KEY="ts_live_xxxxxxxxxxxx"

# Run the test script
node send-email.js
Transactional email Sandbox Ready
import { TrueSend } from '@truesend/node';

const ts = new TrueSend({
  apiKey: process.env.TRUESEND_API_KEY
});

 

if (error) console.error(error);
else console.log('Sent!', data.messageId);

Clean, Predictable API Endpoints

Our API follows a fully RESTful architecture, designed to be simple, consistent, and developer-friendly.

With structured versioning and clear documentation, developers can confidently build integrations knowing future updates won’t disrupt existing implementations.

Versioned Endpoints
Consistent JSON Structure
OpenAPI 3.0 Specification
Interactive API Explorer
OpenAPI Spec Postman Collection Sandbox Mode API Key Auth
Method Endpoint Description
POST /v1/emails/send Send a single email
GET /v1/emails/{id}/events Get email events
GET /v1/templates List all templates
PUT /v1/templates/{id} Update a template
GET /v1/domains List sending domains
POST /v1/webhooks Register a webhook
DELETE /v1/webhooks/{id} Remove a webhook

Real-Time Email Event Notifications

Webhooks allow your application to react immediately to subscriber activity, enabling automation, analytics updates, and real-time workflows powered by email engagement data.

Email.Opened

Triggered when a recipient opens your email on any device or email client.

opened

Email.clicked

A tracked link in your email is clicked

clicked

email.delivered

Confirmed delivery to recipient inbox

delivered
Webhook Payload Example
// POST https://yourapp.com/webhooks/email
// Content-Type: application/json
// X-TrueSend-Signature: sha256=abc123...

{
  "event":      "email.opened",
  "messageId": "msg_01J3K9X2PQ4R7WZ",
  "timestamp": "2026-02-25T10:14:33Z",
  "recipient": {
    "email":   "[email protected]",
    "name":    "John Doe"
  },
  "metadata": {
    "userAgent": "AppleMail/17.0",
    "device":    "desktop",
    "country":   "US",
    "ip":        "192.168.x.x"
  },
  "campaign": {
    "id":       "camp_welcome_series",
    "subject": "Welcome to TrueSend!"
  }
}
14
Event Types
<100ms
Event Delivery

Security Built Into Every Layer

Your API credentials, subscriber data, and sending reputation are safeguarded with enterprise-level security standards.

API Key Scoping

Create API keys with granular access levels. Keys can be rotated instantly without interrupting integrations.

Webhook Signatures

Each webhook request is signed using HMAC-SHA256 signatures.

IP Allowlisting

Limit API access to specific IP addresses or ranges to maintain strict control

Advanced Encryption

All data transmitted between your application and the API is secured with TLS 1.3.

API Key Management

Production Key
ts_live_••••••••••••••••3f7a
Active
Test / Sandbox Key
ts_test_••••••••••••••••9c2b
Sandbox
Analytics Read-Only
ts_live_••••••••••••••••1a4d
Read Only
Recent API Activity
POST /v1/emails/send
200 · 48ms
GET /v1/emails/msg_01J3
200 · 22ms
POST /v1/emails/batch
202 · 91ms
POST /v1/emails/send
429 · Rate Limit

Flexible Limits for Every Scale

Start free and grow without limits. Every plan comes with generous API rate limits and the ability to request increases for high-volume use cases.

Plan Emails / Month API Req / Min Batch Size
Free 3,000 60 100
Pro 100,000 300 500
Business 1,000,000 1,000 1,000
Enterprise Unlimited Custom Custom

Deliver Your Best Work With True Send

  • No Credit Card Needed
  • Unlimited Time On Free Plan