API Overview

Welcome to the Vouch API

The Vouch API provides real-time email validation and fraud detection through a simple REST API. Built on Cloudflare Workers, our API delivers sub-second response times from 275+ global data centers.

Base URL

https://api.vouch.expert

Quick Example

curl -X POST https://api.vouch.expert/validate \
  -H "Authorization: Bearer your_api_key" \
  -H "X-Project-Id: your_project_id" \
  -H "Content-Type: application/json" \
  -d '{"email": "[email protected]"}'

API Versioning

Vouch supports both versioned and unversioned endpoints:

Latest (recommended): /validate - Always uses the current stable version
Versioned: /v1/validate - Locked to API version 1

We recommend using the latest endpoint for new integrations. Versioned endpoints are available for backward compatibility.

Authentication

All API requests require authentication via API keys:

Headers

Authorization

string

required

Bearer token with your API key

Authorization: Bearer your_api_key_here

X-Project-Id

string

required

Your project ID

X-Project-Id: your_project_id

API Key Types

Client Keys

For browser and mobile apps

Restricted to allowed domains
1,000 requests/hour
Safe to expose publicly
Includes device fingerprinting

Server Keys

For backend services

No domain restrictions
5,000 requests/hour
Must be kept secret
Can override IP/User-Agent

Server keys are automatically blocked when used from browsers to prevent accidental exposure.

Rate Limiting

Key Type	Limit	Window
Client Key	1,000 requests	Per hour
Server Key	5,000 requests	Per hour

Rate limits are tracked per project. Exceeding the limit returns a 429 Too Many Requests response with a retryAfter header.

Quota Management

Each subscription includes a monthly validation quota. Monitor your usage via response headers:

X-Quota-Limit: 10000
X-Quota-Used: 2345
X-Quota-Remaining: 7655
X-Quota-Reset: 2024-01-01T00:00:00Z

When quota is exceeded, you’ll receive a 402 Payment Required response.

Endpoints

POST /validate

Validate an email address with fraud detection

Response Format

Validation Response

The /validate endpoint returns a structured response:

{
  "checks": {
    "syntax": { "pass": true, "latency": 2 },
    "disposable": { "pass": true, "latency": 15 },
    "mx": { "pass": true, "latency": 45 }
  },
  "message": null,
  "metadata": {
    "fingerprintHash": "abc123...",
    "previousSignups": 0,
    "totalLatency": 62
  },
  "recommendation": "allow",
  "signals": []
}

Error Response

Error responses return an error object with an HTTP status code:

{
  "error": "Human-readable error message"
}

Error Codes

Code	Status	Description
`INVALID_EMAIL`	400	Email address is required or invalid format
`INVALID_REQUEST`	400	Request body is malformed
`UNAUTHORIZED`	401	Invalid or missing API key
`FORBIDDEN`	403	API key doesn’t have access to project
`QUOTA_EXCEEDED`	402	Monthly validation quota exceeded
`RATE_LIMITED`	429	Too many requests
`INTERNAL_ERROR`	500	Server error (contact support)

Overview

Endpoints

API Overview

Welcome to the Vouch API

Base URL

Quick Example

API Versioning

Authentication

Headers

API Key Types

Client Keys

Server Keys

Rate Limiting

Quota Management

Endpoints

POST /validate

Response Format

Validation Response

Error Response

Error Codes

Complete Error Reference

SDKs

JavaScript

React

Node.js

Next.js

iOS

Android

Support

Email Support

Dashboard

Next Steps

Validate Endpoint

Authentication Guide

Error Handling

Quickstart

​Welcome to the Vouch API

Base URL

​Quick Example

​API Versioning

​Authentication

​Headers

​API Key Types

Client Keys

Server Keys

​Rate Limiting

​Quota Management

​Endpoints

POST /validate

​Response Format

​Validation Response

​Error Response

​Error Codes

Complete Error Reference

​SDKs

JavaScript

React

Node.js

Next.js

iOS

Android

​Support

Email Support

Dashboard

​Next Steps

Validate Endpoint

Authentication Guide

Error Handling

Quickstart

Welcome to the Vouch API

Quick Example

API Versioning

Authentication

Headers

API Key Types

Rate Limiting

Quota Management

Endpoints

Response Format

Validation Response

Error Response

Error Codes

SDKs

Support

Next Steps