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Security for your users.
By your users.

A fully automated approach to account security that lets your good users shape the risk models.

End-to-end solution to account takeover attacks

Castle's suite of security tools are built for one single purpose – protecting your users. Detect automated credential stuffing attacks and human-powered account takeovers, automate the recovery process, and breathe easy with zero false lockouts, support queues, or angry tweets.
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User-trained AI

From credential stuffing botnets to manual takeovers, turn on AI that scales naturally to protect your growing environment.

Account Recovery Automation

No lockouts, complaints, or drops in your core business metrics. Automate a process that works for your app.

Device-level User Analytics

Get transparent insights into every threat signal, risk score, and event tracked per device within a user’s account.

Account Security API

Deconstruct Castle into basic blocks to secure any UX your team dreams up. Security as a user experience.

When it’s this easy, taking responsibility is a no-brainer

Sites and applications that utilize Castle are in a better position to protect, defend, and look out for their users. Our objective: Make it easy for all developers to take on a guardian role. Castle's free trial and entry level plans allow any online business to offer bank-grade account security.
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Worlds leading online brands choose Castle

“A successful integration is one that I don’t have to sit on to use and that can alert us with a minimal amount of false positives. That’s what we have with Castle.”

KEN PICKERING
VP OF ENGINEERING

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“The benefit of Castle is that account takeover is a total non-issue now.”

STEVEN OU CHIEF
TECHNOLOGY OFFICER

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By developers, for developers

No on-prem installations. No single points of failure. Castle’s developer-first platform is built by, and for, those who want to REST easy.
verdict = castle.authenticate(
  event: '$login.succeeded',
  user_id: 'user1234'
)

puts verdict[:action] # => "allow", "challenge" or "deny"
CastleContext context = castle.contextBuilder()
    .fromHttpServletRequest(request)
    .build();

Verdict verdict = castle.client().authenticate(
  CastleMessage.builder("$login.succeeded")
    .context(context)
    .userId("user1234")
    .build()
);

verdict.getAction()
$verdict = Castle::authenticate(array(
  'event' => '$login.succeeded',
  'user_id' => 'user1234'
));

echo $verdict->action;
verdict = castle.authenticate({
    'event': '$login.succeeded',
    'user_id': 'user1234'
})

print(verdict['action']);
const response = await castle.authenticate({
  event: EVENTS.LOGIN_SUCCEEDED,
  user_id: "user1234",
  context: Castle.getContext(request),
});

console.log(response.action);
var result = await castle.Authenticate({
  Event = Events.LoginSucceeded,
  UserId = "user1234",
  Context = Context.FromHttpRequest(Request)
});

Console.WriteLine(result.Action);

See Castle in action

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