Next-gen fingerprinting for modern threat detection
FoxIO’s JA4 and JA4+ are the industry’s most advanced network fingerprinting standards.
R
Next-gen fingerprinting for modern threat detection
FoxIO’s JA4 and JA4+ are the industry’s most advanced network fingerprinting standards.
R
Next-gen fingerprinting for modern threat detection
FoxIO’s JA4 and JA4+ are the industry’s most advanced network fingerprinting standards.
R
The internet is full of fakes. Unmask Every Connection. In Real Time.
Detect bots, proxies, malware, and anonymized traffic — with no client-side JavaScript required.
Used by Fortune 500 companies
Zero JS required – works on APIs, edge devices, and SCADA
12+ unique fingerprinting methods
The internet is full of fakes. Unmask Every Connection. In Real Time.
Detect bots, proxies, malware, and anonymized traffic — with no client-side JavaScript required.
Used by Fortune 500 companies
Zero JS required – works on APIs, edge devices, and SCADA
12+ unique fingerprinting methods
The internet is full of fakes. Unmask Every Connection. In Real Time.
Detect bots, proxies, malware, and anonymized traffic — with no client-side JavaScript required.
Used by Fortune 500 companies
Zero JS required – works on APIs, edge devices, and SCADA
12+ unique fingerprinting methods
What you can do with JA4+
Identify VPNs & Proxies
See clients connecting through residential, corporate, anonymization proxies and VPNs — regardless of source IP.
Estimate Real Client Location
Use FoxIO's patent-pending technology to identify the true client location behind proxies and VPNs.
Detect Bots & Hacking Tools
Stop traffic from tools like AI bots, Evilginx, and Zero Day Exploit Tools.
Secure APIs Without JavaScript
Protect your APIs and web servers from fraud, abuse, credential stuffing, stolen secrets and session hijacking.
Find Malware & C2 Infrastructure
Detect and act on Command & Control activity, remote access tools, screen-sharing apps, and easily find malicious infrastructure.
Expose Rogue Infrastructure
Find rogue devices, unauthorized DHCPv6 servers, and attacker tooling in your environment.
What you can do with JA4+
Identify VPNs & Proxies
See clients connecting through residential, corporate, anonymization proxies and VPNs — regardless of source IP.
Estimate Real Client Location
Use FoxIO's patent-pending technology to identify the true client location behind proxies and VPNs.
Detect Bots & Hacking Tools
Stop traffic from tools like AI bots, Evilginx, and Zero Day Exploit Tools.
Secure APIs Without JavaScript
Protect your APIs and web servers from fraud, abuse, credential stuffing, stolen secrets and session hijacking.
Find Malware & C2 Infrastructure
Detect and act on Command & Control activity, remote access tools, screen-sharing apps, and easily find malicious infrastructure.
Expose Rogue Infrastructure
Find rogue devices, unauthorized DHCPv6 servers, and attacker tooling in your environment.
What you can do with JA4+
Identify VPNs & Proxies
See clients connecting through residential, corporate, anonymization proxies and VPNs — regardless of source IP.
Estimate Real Client Location
Use FoxIO's patent-pending technology to identify the true client location behind proxies and VPNs.
Detect Bots & Hacking Tools
Stop traffic from tools like AI bots, Evilginx, and Zero Day Exploit Tools.
Secure APIs Without JavaScript
Protect your APIs and web servers from fraud, abuse, credential stuffing, stolen secrets and session hijacking.
Find Malware & C2 Infrastructure
Detect and act on Command & Control activity, remote access tools, screen-sharing apps, and easily find malicious infrastructure.
Expose Rogue Infrastructure
Find rogue devices, unauthorized DHCPv6 servers, and attacker tooling in your environment.
Bots create fraud.
Hackers break systems.
AI tools scrape content.
VPNs and proxies mask origins.
FoxIO's JA4+ reveals what’s really going on — before damage is done.
Why Protocol-Layer Threats Bypass Traditional IT Security
Cookie spoofing, proxy chains, and browser impersonation make existing fingerprinting useless.
Traditional security tools miss sophisticated threats that disguise themselves as legitimate traffic.
Client-side fingerprinting is not available for APIs, mobile apps, and IoT devices where JavaScript isn't available.
Attackers easily hide behind residential proxies and VPNs, making threat attribution impossible.
Current tools only detect attacks after damage is done - stolen credentials, compromised APIs, or data breaches.
Why Protocol-Layer Threats Bypass Traditional IT Security
Cookie spoofing, proxy chains, and browser impersonation make existing fingerprinting useless.
Traditional security tools miss sophisticated threats that disguise themselves as legitimate traffic.
Client-side fingerprinting is not available for APIs, mobile apps, and IoT devices where JavaScript isn't available.
Attackers easily hide behind residential proxies and VPNs, making threat attribution impossible.
Current tools only detect attacks after damage is done - stolen credentials, compromised APIs, or data breaches.
Why Protocol-Layer Threats Bypass Traditional IT Security
Cookie spoofing, proxy chains, and browser impersonation make existing fingerprinting useless.
Traditional security tools miss sophisticated threats that disguise themselves as legitimate traffic.
Client-side fingerprinting is not available for APIs, mobile apps, and IoT devices where JavaScript isn't available.
Attackers easily hide behind residential proxies and VPNs, making threat attribution impossible.
Current tools only detect attacks after damage is done - stolen credentials, compromised APIs, or data breaches.
Deployment & Integration
FoxIO’s patent pending fingerprinting and detection technologies integrate seamlessly into your existing infrastructure through libraries, SDKs, or direct SIEM integration. We provide native support for popular platforms including Zeek, Suricata, and major security and cloud providers.
Fingerprint Traffic at the Protocol Layer
FoxIO's JA4+ fingerprints traffic by analyzing how connections behave — not just what they claim to be. It works beneath the application layer to surface insight where traditional tools can’t reach.
JA4
TLS Client Fingerprinting
JA4S
TLS Server Response / Session Fingerprinting
JA4H
HTTP Client Fingerprinting
JA4L
Client to Server Latency / Light Distance
JA4LS
Server to Client Latency / Light Distance
JA4X
X509 TLS Certificate Fingerprinting
JA4SSH
SSH Traffic Fingerprinting
JA4T
TCP Client Fingerprinting
JA4TS
TCP Server Response
+9 More..
Fingerprint Traffic at the Protocol Layer
FoxIO's JA4+ fingerprints traffic by analyzing how connections behave — not just what they claim to be. It works beneath the application layer to surface insight where traditional tools can’t reach.
JA4
TLS Client Fingerprinting
JA4S
TLS Server Response / Session Fingerprinting
JA4H
HTTP Client Fingerprinting
JA4L
Client to Server Latency / Light Distance
JA4LS
Server to Client Latency / Light Distance
JA4X
X509 TLS Certificate Fingerprinting
JA4SSH
SSH Traffic Fingerprinting
JA4T
TCP Client Fingerprinting
JA4TS
TCP Server Response
+9 More..
Fingerprint Traffic at the Protocol Layer
FoxIO's JA4+ fingerprints traffic by analyzing how connections behave — not just what they claim to be. It works beneath the application layer to surface insight where traditional tools can’t reach.
JA4
TLS Client Fingerprinting
JA4S
TLS Server Response / Session Fingerprinting
JA4H
HTTP Client Fingerprinting
JA4L
Client to Server Latency / Light Distance
JA4LS
Server to Client Latency / Light Distance
JA4X
X509 TLS Certificate Fingerprinting
JA4SSH
SSH Traffic Fingerprinting
JA4T
TCP Client Fingerprinting
JA4TS
TCP Server Response
+9 More..
Built for Engineers. Trusted by Enterprises.
FoxIO's JA4+ is used by teams at Walmart, Amazon, and McKesson. It’s API-ready, actively maintained, and supports open-source integration for custom deployment across your stack.
Built for Engineers. Trusted by Enterprises.
FoxIO's JA4+ is used by teams at Walmart, Amazon, and McKesson. It’s API-ready, actively maintained, and supports open-source integration for custom deployment across your stack.
Built for Engineers. Trusted by Enterprises.
FoxIO's JA4+ is used by teams at Walmart, Amazon, and McKesson. It’s API-ready, actively maintained, and supports open-source integration for custom deployment across your stack.
See What’s Really Hitting Your Servers
Start fingerprinting traffic and protecting your infrastructure — with no script injection or browser fingerprinting required. Book a demo call today.
See What’s Really Hitting Your Servers
Start fingerprinting traffic and protecting your infrastructure — with no script injection or browser fingerprinting required. Book a demo call today.
See What’s Really Hitting Your Servers
Start fingerprinting traffic and protecting your infrastructure — with no script injection or browser fingerprinting required. Book a demo call today.
Beyond a JA4+ DB — the FoxIO Platform
FoxIO is building a next-generation traffic intelligence platform. While FoxIO’s JA4+ is the foundation, the platform extends beyond JA4+ to deliver advanced detection, automation, and integration for modern enterprises.
Beyond a JA4+ DB — the FoxIO Platform
FoxIO is building a next-generation traffic intelligence platform. While FoxIO’s JA4+ is the foundation, the platform extends beyond JA4+ to deliver advanced detection, automation, and integration for modern enterprises.