# HTTP3/QUIC Protocol Support

Source: https://docs.evomi.com/proxy-instructions/residential-proxies/expert-settings/http3/

**Note:** Expert settings are only available for **Core Residential Proxies**.

Evomi Residential Proxies support HTTP3/QUIC for improved performance and compatibility with modern websites. This feature helps requests use the same current web protocols supported by modern browsers.

**SOCKS5 Protocol Required**  
HTTP3/QUIC support is only available when using the SOCKS5 protocol. This feature will not work with HTTP/HTTPS proxy protocols. Make sure your client supports SOCKS5 connections.

**Critical: Use udp.evomi.com hostname only**  
For HTTP3 connections, you MUST use the hostname `udp.evomi.com` exclusively. No other hostnames will work for HTTP3.

## Why HTTP3/QUIC Matters
Modern browsers automatically negotiate HTTP3 connections, and websites increasingly rely on this capability. HTTP3/QUIC support helps automated workflows maintain protocol compatibility with sites that use current web standards.

### Key Benefits
- **Modern Browser Compatibility**: Supports the HTTP3 capabilities available in current browsers
- **Enhanced Performance**: Reduced latency and improved connection reliability
- **Future-Proof**: Support for the latest web protocol standards
- **Consistent Protocol Behavior**: Reduces compatibility differences when a website expects HTTP3 support

## Implementation
Append `_http3-1` to your proxy password to enable HTTP3/QUIC protocol support. Use the SOCKS5 protocol:

<!--email_off-->
```bash
socks5://testuser:testpassword_http3-1@udp.evomi.com:1002
```
<!--email_on-->

## Examples

#### CURL

  ```bash
# Using SOCKS5 protocol with UDP hostname for HTTP3
curl --socks5 udp.evomi.com:1002 -U testuser:testpassword_http3-1 https://ip.evomi.com/s

# Combined with geographic targeting
curl --socks5 udp.evomi.com:1002 -U testuser:testpassword_country-US_http3-1 https://ip.evomi.com/s
```

#### Python

  ```Python
import requests
from requests.auth import HTTPProxyAuth

proxies = {
  "http": "socks5://udp.evomi.com:1002",
  "https": "socks5://udp.evomi.com:1002"
}
auth = HTTPProxyAuth("testuser", "testpassword_http3-1")
response = requests.get("https://ip.evomi.com/s", proxies=proxies, auth=auth)
print(response.text)
```

#### JavaScript

```JavaScript
const fetch = require('node-fetch');
const { SocksProxyAgent } = require('socks-proxy-agent');

const proxyPass = 'testpassword_http3-1';
const proxyUrl = `socks5://testuser:${proxyPass}@udp.evomi.com:1002`;
const agent = new SocksProxyAgent(proxyUrl);
const url = 'https://ip.evomi.com/s';

fetch(url, { agent })
  .then(res => res.text())
  .then(body => console.log(body));
```

## Technical Details
- **Protocol**: HTTP/3 over QUIC (UDP-based)
- **TLS**: Integrated TLS 1.3 encryption
- **Multiplexing**: Stream-level multiplexing without head-of-line blocking
- **Connection Migration**: Robust connection handling across network changes
- **Protocol Requirement**: SOCKS5 protocol only (not compatible with HTTP/HTTPS proxies)

## Common Use Cases
- **Web Data Collection**: Work with websites that prefer or require modern protocols
- **Browser Automation**: Maintain current browser protocol compatibility
- **Performance Testing**: Evaluate HTTP3 performance characteristics
- **Security Research**: Test HTTP3-specific security implementations
- **E-commerce Monitoring**: Monitor modern storefronts that use HTTP3
- **SEO Analysis**: Crawl websites using current transport protocols

**Protocol Compatibility**  
HTTP3/QUIC is backward compatible. If the target server doesn't support HTTP3, connections automatically fall back to HTTP/2 or HTTP/1.1. Use our [Proxy Generator](https://docs.evomi.com/proxy-instructions/proxy-generator/) to test HTTP3 compatibility with specific targets.

**Note:** The http3 parameter is an extra feature. Using it will incur additional bandwidth consumption. You can see the exact extra usage history in the dashboard and in the Generator.

**Example Configurations**
Combine HTTP3 with targeting and quality parameters when needed:
`_http3-1_fraudscore-0_device-windows`  
`_country-US_http3-1_isp-comcast_latency-100`  
`_zip-90210_http3-1_device-apple`