TLS Fingerprinting

TLS fingerprinting is critical for bypassing bot detection. Standard HTTP libraries will be detected and blocked.

Why It Matters

Akamai and other bot detection systems analyze your TLS handshake to identify:

• Cipher suites offered

• TLS extensions and their order

• Supported curves and signature algorithms

• HTTP/2 settings and priorities

If your fingerprint doesn't match a real browser or device, you'll be blocked.

Required: TLS Client

Use bogdanfinn/tls-client instead of standard HTTP libraries.

Installation

Go

Install (Go)

go get github.com/bogdanfinn/tls-client

Python

JavaScript

Basic Usage

Go

Go example

import (
    http "github.com/bogdanfinn/fhttp"
    tls_client "github.com/bogdanfinn/tls-client"
)

client, err := tls_client.NewHttpClient(tls_client.NewNoopLogger(),
    tls_client.WithClientProfile(tls_client.Chrome_120),
)

req, _ := http.NewRequest("GET", "https://example.com", nil)
resp, err := client.Do(req)

Python

Chrome 108+ Note

For Chrome 108 and later, enable random TLS extension order:

Go (enable random extension order)

tls_client.WithRandomTLSExtensionOrder()

Python (enable random extension order)

session = tls_client.Session(random_tls_extension_order=True)

Verifying Your Fingerprint

1

Make the request to the fingerprint API

Request: https://tls.peet.ws/api/all

2

Make the same request from a real browser

Perform the same request in the target browser for comparison.

3

Compare the results

Use https://www.diffchecker.com/ to compare the outputs.

Key fields to match:

• ja3 / ja3_hash

• akamai_fingerprint

• http2_settings

Common Issues

Issue	Solution
Fingerprint mismatch	Update client profile to match target browser
Random blocking	Enable random extension order for Chrome 108+
HTTP/2 issues	Verify HTTP/2 settings match browser

Resources

• bogdanfinn/tls-client — TLS client library

• HTTP/2 Fingerprinting Paper — Technical deep dive

• tls.peet.ws — Fingerprint checker