Stop bots and account abuse at scale

Expose coordinated abuse with Castle's device, email, IP and behavioral intelligence. Enterprise security without the friction.

Everything you need to stop fraud & abuse

A complete stack of data, tools, and APIs, eliminating the need for multiple, disconnected tools. All the intelligence you need to stop fraud and abuse.

IP Intelligence

Assess IP reputation and risk. Detect proxies, VPNs, Tor, and datacenter traffic.

{
  "address": "1.0.105.13",
  "type": "ipv4",
  "asn": 18144,
  "location": {
    "continent_code": "AS",
    "country_code": "JP"
  },
  "tunnels": [
    {
      "type": "proxy",
      "operator": "FloppyData residential",
      "tier": null,
      "last_seen_at": "2026-06-25T21:38:40.000Z",
      "proxy_type": "residential"
    },
    {
      "type": "proxy",
      "operator": "AnyIP residential",
      "tier": null,
      "last_seen_at": "2026-06-21T22:55:42.000Z",
      "proxy_type": "residential"
    }
  ]
}

Device fingerprinting

99.5% accurate fingerprinting. Uncover headless browsers, tampering, carrier data, etc.

Bot detection

Detect bots, scripts, and coordinated attacks. Identify automated behavior and tampering.

AI scoring

Spot account takeover attempts and abusive behavior using self-learning AI.

Abuse Score: 90
Account Takeover Score: 75
Bot Score: 12

Behavioral analysis

Use out-of-the-box signals or create your own custom aggregations and rate limiters.

• Bot behavior
• Generated email
• Abuse IP
• Multiple accounts per device
• New country
• Credential stuffing
• New device
• High activity account
• Web crawler
• Impossible travel
• New language
• Disposable email domain
• Datacenter IP
• Emulated device
• High activity device
• Headless browser
• High activity IP
• HTTP client library
• Invalid device data
• Invalid email
• Low quality email
• Missing device data
• Missing headers
• Residential proxy
• Multiple aliases per email
• New device type
• New ISP
• New OS
• Outdated SDK version
• Phone call active
• Proxy IP
• Replayed device data
• Residential proxy IP
• Rooted device
• Spoofed device
• Timezone area mismatch

Email intelligence

Assess email reputation and risk. Detect disposable domains and enumeration patterns.

Example: ma.ken.na493+2@tenermail.com

Case & state management

Manage dynamic trust, block, and review lists of users, devices, or any custom attribute.

• Blocked users
• Trusted users
• Account sharing
• Whitelisted emails
• Blacklisted IPs

Advanced user behavior analytics

Monitor, analyze, and alert on up to 18 months of historical data enriched with user and device intelligence to stop evolving abuse trends.

Customization

Fraudulent behavior, as defined by you. Combine Castle's threat data with velocity checks and rate limiters to categorize users according to what's considered fraud and abuse on your specific platform.

Automation

Scale threat response with custom flows. Model custom security flows, blocklists, and trusted device management. Manage review states across signups, logins, and in-app activity.

State management

Maintain blocklists, allowlists, and trusted devices—updating states in real-time from rules or manual actions.

Inline blocking

Initiate real-time blocks or step-up verifications anywhere in your app without disrupting the user experience.

Alerts & notifications

Keep your team informed with Slack alerts, or automate end-user and internal workflows with granular webhooks.

Developers

Integrate selected data points with your business logic. Or rely on our rules engine and state management for a complete fraud and abuse solution.

{
  "id": "2V48MDnuMar9pvOOwulwK4BXui2",
  "type": "$login",
  "status": "$succeeded",
  "name": "Login Succeeded",
  "authenticated": true,
  "endpoint": "/v1/risk",
  "created_at": "2025-09-02T4:39:05.147Z",
  "properties": {
    "my_custom_property": 234
  },
  "device": {...},
  "email": {...},
  "metrics": {...},
  "signals": {...},
  "policy": {...},
  "lists": [...],
  "user": {...}
}

Built for scale

Our APIs process billions of monthly requests with resilience against severe bot attacks.

100ms response time

Fingerprinting, risk scores, and rules computed instantly in real-time.

Pay-as-you-go pricing

Transparent plans with included API budgets and simple pay-as-you-go pricing.

Get started

Create your free account today with transparent pricing that scales when you do.