Castle Overview
Castle is a comprehensive, developer-first security platform designed to provide the trust infrastructure for the modern internet. It empowers businesses to protect themselves from a wide array of sophisticated threats, including automated bots, credential stuffing, account takeovers (ATO), fake account creation, and content abuse. Trusted by leading companies like Canva, Rockstar Games, and Atlassian, Castle offers a robust solution that operates seamlessly in the background to secure user accounts and platform integrity.
The core of Castle's effectiveness lies in its unique dual-layer fraud defense architecture. This system combines edge-level protection, which can be deployed with no code via a Cloudflare integration, with deep in-app monitoring through powerful SDKs. Signals flow between these two layers, creating a unified defense system where early-stage blocking at the edge sharpens the detection of more subtle threats within the application. This approach ensures comprehensive coverage against evolving attack vectors.
How to use Castle
Integrating Castle is designed to be fast and straightforward, allowing businesses to go live in minutes.
- Sign Up & Choose a Plan: Create a free account to start. You can evaluate the platform with up to 1,000 API calls per month.
- Integration: Choose your preferred integration method. For rapid deployment, connect Castle to your Cloudflare stack with no code required. For deeper insights and control, integrate Castle's lightweight SDKs (available for web and mobile) into your application's backend and frontend.
- Monitor and Analyze: Initially, you can run Castle in 'monitoring mode'. This allows you to observe user behavior, device data, and risk scores without actively blocking traffic. The analytics dashboard provides deep insights into potential threats and user patterns.
- Configure Policies: Use the intuitive Rules Engine to create custom logic. Define rules to allow, challenge (e.g., with MFA), or deny actions based on risk scores, behavioral signals, device fingerprints, or any custom data.
- Activate Protection: Once you are confident in your rules, switch to 'blocking mode' to actively prevent fraud and abuse in real-time, securing critical user flows like signups, logins, and transactions.
Core Features of Castle
- Dual-Layer Fraud Defense: Combines edge and in-app security for holistic threat detection.
- AI-Powered Risk Scoring: Self-learning AI models that score the risk of account takeover, bot activity, and general abuse in real-time.
- Advanced Device Fingerprinting: Achieves 99.5% accuracy in identifying unique devices, detecting headless browsers, emulators, and device tampering.
- Behavioral Analysis: Tracks user sessions, device interactions, and behavior, enriched with your business context to spot anomalies.
- Real-time Rules Engine: Allows you to build and manage complex risk logic to allow, challenge, or deny actions without deploying new code.
- Comprehensive Analytics: A powerful suite for proactive threat hunting, network analysis, session monitoring, and backtesting rules on historical data.
- Email & IP Intelligence: Assesses email reputation, detects disposable domains, and analyzes IP risk, including proxy and Tor detection.
- Developer-First API: A single, well-documented API to retrieve threat insights and orchestrate security responses across your entire stack.
Use Cases for Castle
Castle is versatile and can be applied to protect various aspects of an online platform:
- Account Takeover (ATO) Prevention: Identifies and blocks credential stuffing attacks and suspicious login attempts from unfamiliar devices or locations.
- Fake Account & Signup Fraud: Weeds out bots and malicious actors at the registration stage by analyzing email reputation, IP risk, and behavioral patterns.
- Multi-Accounting Prevention: Prevents users from creating multiple accounts to abuse promotions, referral programs, or community guidelines.
- Content & Spam Abuse: Automatically blocks repetitive, low-quality, or malicious content submitted by bots or bad actors.
- Transaction & Payment Fraud: Stops credit card testing, promo abuse, and other forms of financial fraud.
- SMS Pumping Elimination: Protects against abuse of SMS-based two-factor authentication, which can lead to inflated costs.
Advantages of Castle
Castle provides a significant competitive edge through its modern approach to security:
- Frictionless Security: Operates silently, ensuring that legitimate users have a smooth experience while only high-risk interactions are challenged.
- Rapid Deployment: Go from signup to active protection in minutes, not months.
- High Scalability: The infrastructure is built to process billions of monthly requests with a median response time of 100ms.
- Unified Platform: Eliminates the need for multiple, disconnected security tools by providing a complete stack of data, APIs, and management tools.
- Transparent & Predictable Pricing: Offers a clear pay-as-you-go model that scales with your business needs.
Pricing and Plans
Castle offers a flexible, transparent pricing structure suitable for businesses of all sizes.
- Free Plan: $0/month. Includes up to 1,000 API calls per month, 3 seats, 1 environment, and 3 days of data exploration. Ideal for evaluation and small projects.
- Pro Plan: Starts at $200/month for the first 100,000 API calls. Includes 5 seats, 2 environments, 7 days of data exploration, and chat/email support. Designed for production applications.
- Enterprise Plan: Custom pricing starting at $4,000/month. Offers unlimited API calls, up to 18 months of data history, unlimited seats, dedicated support with a Slack channel, SLAs, and the option for pricing based on Monthly Tracked Users (MTU).
Traffic
Latest traffic
Status
Monthly traffic trend
- 2025-9: 52.2K
- 2026-1: 75.0K
- 2026-2: 48.7K
- 2026-3: 51.2K
- 2026-4: 52.8K
- 2026-5: 47.6K
Geography
Top 5 countries / regions
- 🇮🇳India67.0%
- 🇺🇸United States14.3%
- 🇻🇳Vietnam8.8%
- 🇷🇺Russia6.0%
- 🇵🇰Pakistan3.9%
Traffic sources
| Source type | Percentage |
|---|---|
Direct | 82.9% |
Referral | 9.9% |
Email | 7.1% |
Top keywords
| Keyword | Cost per click |
|---|---|
| castle | $0.72 |
| castle app | $0.21 |
| castle app login | $0.00 |
| castle login | $0.00 |
| castle web | $0.00 |
Castle Alternatives
Sift
Sift is an AI-powered Digital Trust & Safety platform that helps businesses prevent fraud and abuse. Using real-time machine learning and a global data network, it protects against payment fraud, account takeovers, and content spam. Sift enables companies to grow securely by accurately identifying and stopping malicious activity while reducing friction for legitimate users, ultimately building trust and safety online.
Risk Management
LoginLlama
LoginLlama is an AI-powered API for developers that detects suspicious logins in real-time. By analyzing user behavior, IP origin, and other factors, it helps prevent account takeovers, credential stuffing, and phishing attacks. Integrate with a few lines of code to enhance your application's security and build customer trust.
Api
greip
Greip is an AI-powered fraud prevention platform that helps online businesses detect and block fraudulent activities in real-time. It utilizes advanced techniques like device fingerprinting, behavioral analysis, and IP intelligence to provide comprehensive security, reduce chargebacks, and protect user accounts.
Analytics
trestleiq
TrestleIQ provides enterprise-grade identity data enrichment and validation APIs. It helps businesses maximize customer contactability, verify identities, and prevent fraud by offering real-time data on phone numbers, addresses, and individuals. Leveraging machine learning, TrestleIQ delivers accurate, low-latency insights for lead generation, customer service, and compliance, accessible via easy-to-integrate APIs or batch uploads.
Api
Tilores
Tilores is an AI-powered, no-code identity resolution platform designed for fraud prevention, KYC, and AML. It provides a real-time API to unify scattered customer data from various sources, creating a single, accurate view of each entity. This helps businesses detect complex fraud patterns, streamline compliance, and make better data-driven decisions without extensive engineering effort.
AnalyticsCastle Categories
Castle Embed Widget
Copy this embed code to place the badge on your blog, article, or product site and send readers directly to this ToolMage detail page.
Related AI tools
Sift
Sift is an AI-powered Digital Trust & Safety platform that helps businesses prevent fraud and abuse. Using real-time machine learning and a global data network, it protects against payment fraud, account takeovers, and content spam. Sift enables companies to grow securely by accurately identifying and stopping malicious activity while reducing friction for legitimate users, ultimately building trust and safety online.
Risk ManagementLoginLlama
LoginLlama is an AI-powered API for developers that detects suspicious logins in real-time. By analyzing user behavior, IP origin, and other factors, it helps prevent account takeovers, credential stuffing, and phishing attacks. Integrate with a few lines of code to enhance your application's security and build customer trust.
Api
Roundtable
Roundtable is an AI-powered security platform that offers an invisible, privacy-first alternative to CAPTCHA. It uses continuous behavioral AI to detect and block bots and fraudulent activity in real-time, ensuring seamless user experience and robust data integrity without intrusive challenges.
Authentication
gueno
gueno is an all-in-one, AI-powered platform for fraud prevention and compliance, specifically designed for Fintech and Crypto companies operating in Latin America. It provides real-time monitoring, user onboarding, and transaction validation for both FIAT and crypto through a single, easy-to-integrate API, helping businesses increase conversion while minimizing risk.
Fraud Detectiongreip
Greip is an AI-powered fraud prevention platform that helps online businesses detect and block fraudulent activities in real-time. It utilizes advanced techniques like device fingerprinting, behavioral analysis, and IP intelligence to provide comprehensive security, reduce chargebacks, and protect user accounts.
Analyticstrestleiq
TrestleIQ provides enterprise-grade identity data enrichment and validation APIs. It helps businesses maximize customer contactability, verify identities, and prevent fraud by offering real-time data on phone numbers, addresses, and individuals. Leveraging machine learning, TrestleIQ delivers accurate, low-latency insights for lead generation, customer service, and compliance, accessible via easy-to-integrate APIs or batch uploads.
ApiTilores
Tilores is an AI-powered, no-code identity resolution platform designed for fraud prevention, KYC, and AML. It provides a real-time API to unify scattered customer data from various sources, creating a single, accurate view of each entity. This helps businesses detect complex fraud patterns, streamline compliance, and make better data-driven decisions without extensive engineering effort.
Analytics
Jyek
Jyek is an AI agent platform that understands objectives, creates execution plans, uses tools, and delivers verifiable results for complex, multi-step tasks.
Automation
Quick Intel
Quick Intel is an AI-powered security platform for the Web3 space, providing real-time smart contract analysis for crypto traders and developers. It scans contracts across dozens of blockchains to detect hidden risks, potential scams, and honeypots, empowering users to make safer investment decisions.
Api
AuthentiCheck
AuthentiCheck provides a real-time API to detect and block fake, temporary, and disposable email addresses. It helps protect platforms from fraudulent sign-ups, phishing attacks, and spam, while improving email list quality and deliverability rates for marketing campaigns. Its robust system ensures genuine user engagement and enhances data accuracy.
Api
Veriff
Veriff is an AI-powered identity verification and fraud prevention platform. It helps businesses build trust online by offering fast, accurate, and secure verification of customer identities. Supporting over 12,000 documents from 230+ countries, Veriff provides solutions for KYC/AML compliance, age verification, and biometric authentication, ensuring a seamless user onboarding experience while minimizing risk.
Kyc & Aml
facia
Facia is an advanced AI-powered identity verification and security platform. It specializes in deepfake detection, liveness detection, and age verification using facial biometrics. Designed for businesses, it helps prevent fraud, ensure regulatory compliance (like KYC and COPPA), and secure online interactions across various industries.
Api
TypingDNA
TypingDNA offers advanced user authentication through typing biometrics. It verifies users based on their unique typing patterns, providing a frictionless and secure alternative to traditional 2FA. Its solutions include a ready-to-use 2FA product and a flexible Authentication API for custom integrations, enhancing security for finance, education, and enterprise applications without compromising user experience.
Api
IDWise
IDWise is a next-generation, AI-powered identity verification suite designed for global businesses. It offers rapid and secure customer onboarding by supporting over 13,000 ID documents from 200+ countries, combined with bank-grade facial biometrics, liveness detection, and comprehensive e-KYC/AML compliance checks. It's built to maximize conversion rates while minimizing fraud.
Api
Luxand.cloud
A powerful AI-powered cloud API for developers and businesses, providing advanced face recognition, liveness detection, and demographic analysis (age, gender, emotion). Easily integrate biometric features into any website, app, or software with a secure, scalable, and cost-effective solution.
Computer Vision
Castle Comments (0)
Sign in to comment.
Sign inNo comments yet.