M
API Matrix

HTTP2.Pro API

⭐ Beginner's Pick Development / No Auth Required Beginner HTTPS
Free to Use Varies (check documentation)
72 Score
Grade B
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Overview

HTTP2.Pro is a testing service that lets you verify whether a client or server supports the HTTP/2 protocol via a simple API call. It returns protocol negotiation results and connection metadata in JSON. Useful for automated CI checks to confirm your web server is properly serving HTTP/2.

💡

Beginner Tip

No authentication is required. Send a GET request with a url parameter pointing to the server you want to test, and the API responds with whether HTTP/2 was negotiated. It is a single-endpoint API, making it very easy to learn from.

Available Data

HTTP2.Pro data via REST API
JSON-formatted response data
Freely accessible without authentication

Example Response

JSON Response 
{
  "status": "success",
  "data": {
    "result": "Data from HTTP2.Pro",
    "description": "Test endpoints for client and server HTTP/2 protocol support",
    "timestamp": "2025-01-15T10:00:00Z"
  }
}

Field Reference

url The URL that was tested for HTTP/2 support.
h2 1 if HTTP/2 was negotiated successfully, 0 otherwise.
protocol The actual protocol negotiated (e.g., h2, http/1.1).
push 1 if HTTP/2 server push is supported, 0 otherwise.

Implementation Example 

// ⚠️ Note: This URL may be a documentation page. Check official docs for actual API endpoint.
const url = "https://http2.pro/doc/api";
const response = await fetch(url);
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

Timeout or connection error The target server is slow to respond or blocks external probes
✓ Test with a well-known HTTPS domain like https://www.google.com first to confirm the API is working.
h2 field is false or 0 The target server does not support HTTP/2
✓ This is an expected result, not an error — it means the server only supports HTTP/1.1.
400 Bad Request URL parameter is missing or malformed
✓ Ensure the url parameter is present and properly URL-encoded.

Matrix Score Breakdown

🌐 Reachability 30/30
⚡ Speed 5/20
🔒 Security 15/15
🛠 Developer XP 15/20
✓ Reliability 7/15
Response Time 2230ms

Fully tested on Apr 5, 2026

Technical Specifications

Auth No Auth
HTTPS REQUIRED
CORS UNKNOWN
Category Development
Difficulty Beginner
Verified: 2026-04-07

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