ImprovMX API

Email / API Key Intermediate HTTPS
Varies by plan (check documentation)

Overview

ImprovMX is an email forwarding service with a REST API that lets you programmatically manage domains and forwarding rules — mapping email aliases to real destination addresses. It is useful for adding custom domain email to projects without running a mail server. An API key is required; a free tier allows one domain with up to 25 aliases.

💡

Beginner Tip

ImprovMX is not for sending or receiving raw email — it forwards mail from a custom domain (e.g., [email protected]) to an existing inbox. The API lets you add and update these forwarding rules programmatically rather than through the web dashboard.

Available Data

email delivery status
message ID
bounce/complaint data
open/click tracking

Example Response

JSON Response
{
  "message_id": "msg_abc123def456",
  "status": "delivered",
  "to": "[email protected]",
  "subject": "Welcome!",
  "timestamp": "2025-01-15T10:30:00Z"
}

Field Reference

success Indicates whether the API request was processed successfully
domains List of domain objects associated with your account, each containing domain name, aliases, and plan info
domain.domain The registered domain name (e.g., example.com) configured in ImprovMX
domain.aliases Array of alias objects for the domain, each with alias (local part) and forward (destination email) fields
domain.active Whether the domain is currently active and forwarding emails
errors Key-value map of validation errors returned when a request fails (e.g., invalid email format)

Implementation Example

// ⚠️ Note: This URL may be a documentation page. Check official docs for actual API endpoint.
const url = "https://improvmx.com/api";
// Replace headers or query params with the values required by this API.
const response = await fetch(url, {
  headers: {
  "X-API-Key": "YOUR_API_KEY"
  }
});
if (!response.ok) throw new Error(`Request failed: ${response.status}`);
const data = await response.json();
console.log(data);

What Can You Build?

Note: These code examples are AI-generated and unverified. Always refer to the official API documentation for accurate usage.

Common Errors & Troubleshooting

401 Unauthorized on all requests ImprovMX uses HTTP Basic Auth with api as the username and your API key as the password
Format your Authorization header as Basic base64("api:YOUR_API_KEY") — not as a Bearer token
Domain not found (404) after adding via web UI The API and web dashboard share the same account, but domain names must match exactly including any subdomain prefix
List your domains first with GET /domains to confirm the exact domain string before making alias requests
Alias limit exceeded (422 error) The free plan caps the number of aliases per domain
Upgrade the plan for the domain in the ImprovMX dashboard or remove unused aliases via DELETE /domains/{domain}/aliases/{alias}

Matrix Score Breakdown

🌐 Reachability 30/30
⚡ Speed 15/20
🔒 Security 15/15
🛠 Developer XP 12/20
✓ Reliability 10/15

Partially tested on Apr 5, 2026

Technical Specifications

Auth API Key
HTTPS REQUIRED
CORS UNKNOWN
Category Email
Difficulty Intermediate
Verified: 2026-04-04

Alternatives to ImprovMX

Technical alternatives for different use cases.

Email forwarding for custom domains

Better For

Bulk email sending and marketing automation

Trade-off

Simple email forwarding without full email service

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