← All website monitoring tools
Castle
Account-takeover prevention + bot detection — published pricing from $499/mo.
What it does well
- Provides real-time risk scores for user actions via an API-first integration.
- Device fingerprinting helps identify returning users even after they clear their cookies.
- Logs provide a detailed, human-readable history of a user's security-related events.
Where it falls short
- High starting price of $499/month makes it inaccessible for smaller projects.
- No free tier or trial is publicly offered for testing before purchase.
- Requires developer effort to integrate and send event data; not a plug-and-play tool.
Alternatives to Castle
Fingerprint (FingerprintJS)
freemiumBrowser fingerprinting library + paid Pro API — free OSS core, paid plans from $99/mo.
Google reCAPTCHA Enterprise
freemiumGoogle's enterprise captcha + risk scoring — first 10K assessments/mo free, $1/1K above.
DataDome
paidReal-time bot protection at the edge — quote-based, typical SMB starts ~$2,000/mo.
Seon
freemiumAPI-first fraud screening with social-media + email enrichment — published from $599/mo.