Sending millions of emails needs testing infrastructure before mass deployment. Our sandbox systems help businesses stay compliant with GDPR, CAN-SPAM and Data protection standards.
Let's test, fix, and improve every part of email campaigns before going live.
Call any endpoint with your API key. RESTful, predictable, and fast.
TrueSend fetches data, runs spam analysis, validates HTML, and checks auth.
Get structured JSON with emails, scores, headers, and validation results.
Test email content, subject lines, templates, and personalization before sending real campaigns.
Test welcome emails, cart recovery, and drip flows automatically and make sure every trigger works correctly at the right moment.
Send sample API calls and quickly evaluate the results to guarantee proper integration and data flow.
Make test contacts and set off events such as clicks, purchases, or signups. This will safely test actual campaign behaviour.
Check how your emails look across multiple devices and inbox clients. Don't compromise on formatting & design.
Track all test activities, API responses, and errors to quickly identify and fix issues before production.
Start using the sandbox API in 3 simple steps.
Enter your ESP account to reach sandbox tools and settings.
Create secure test credentials that allow you to safely use the sandbox environment.
Utilize the built-in testing tool to test API calls and email operations.Utilize the built-in testing tool to test API calls and email operations.
Lastly, review responses, check errors, and fix them before moving to production campaigns.
Get started with TrueSend's Sandbox API using SDKs for Node.js, Python, PHP, Ruby, Go, and Java, or connect directly via the REST API in any programming language.
Full API Docs// Node.js SDK — Quick Start const { TrueSend } = require('truesend'); const client = new TrueSend('ts_live_a1b2c3d4'); // Fetch latest emails const emails = await client.messages.list({ inbox_id: 'inbox_9f8e7d6c', to: 'user@example.com' }); // Check the first email const msg = emails.data[0]; console.log(msg.subject); // → "Welcome to MyApp!" console.log(msg.spam_score); // → 0.8
Unlock a complete set of built-in utilities to support safe testing, debugging, and optimization of email campaigns.
Generate and manage API keys and secrets for secure access to the sandbox environment.
Learn MoreSend controlled test emails without reaching real users to validate content and delivery flow.
Learn MoreEverything you need to know about TrueSend's Sandbox API