# Gurdx API Documentation

> Gurdx is a fraud-prevention and user-intelligence API, a drop-in REST API with a standard JSON response format. Base URL:https://gurdx.cretip.com/api

## Docs

- [Introduction](https://gurdx.cretip.com/en/docs/introduction): Gurdx is a fraud-prevention and user-intelligence API that scores IP addresses, emails, phone numbers, cards, IBANs and payments in a single JSON call.
- [Authentication](https://gurdx.cretip.com/en/docs/authentication): Every Gurdx request must carry an API key, sent either as a query parameter or as a Bearer token.
- [HTTPS](https://gurdx.cretip.com/en/docs/https): Gurdx is served over HTTPS so that your API keys and the data you send are encrypted in transit.
- [API Keys](https://gurdx.cretip.com/en/docs/api-keys): Create, scope, rotate and protect the keys that authenticate your calls to Gurdx.
- [Error Codes](https://gurdx.cretip.com/en/docs/error-codes): Every error Gurdx can return, with its code, type and meaning, and how to handle them in your code.
- [Usage Limits](https://gurdx.cretip.com/en/docs/usage-limits): How many requests your plan includes, how the per-second flood limit works and which calls are free.
- [API Policy](https://gurdx.cretip.com/en/docs/api-policy): How Gurdx versions its API, announces changes and retires old behaviour, so you can plan upgrades.
- [Customize Modules](https://gurdx.cretip.com/en/docs/options/customize-modules): Use the params parameter to ask for exactly the extra data you need and keep responses small.
- [Response Format](https://gurdx.cretip.com/en/docs/options/response-format): Choose how Gurdx encodes the response: JSON, XML, CSV or plain newline-separated values.
- [Localization](https://gurdx.cretip.com/en/docs/options/localization): Use the lang parameter to receive translated fields in your users' language.
- [Development Environment](https://gurdx.cretip.com/en/docs/options/development-environment): Build and test your integration for free with test mode, which never touches your quota or your event feed.
- [User Identifier](https://gurdx.cretip.com/en/docs/options/user-identifier): Attach your own user reference to a request so that risky events in the dashboard point back to a real person in your system.
- [JSONP Callback](https://gurdx.cretip.com/en/docs/options/jsonp-callback): Wrap a JSON response in a JavaScript function call so that it can be loaded with a script tag.
- [VPN and Proxy Detection](https://gurdx.cretip.com/en/docs/options/vpn-proxy-detection): Add the security module to an IP request to learn whether the visitor is hiding behind a VPN, proxy or Tor.
- [API Reference](https://gurdx.cretip.com/en/docs/api-reference/index): Every Gurdx API method, its inputs, its response and the rules that apply to every call.
- [IP Geolocation](https://gurdx.cretip.com/en/docs/api-reference/geoip): Returns the location, network, timezone, currency and security profile of the visitor who is calling your API.
- [IP Lookup](https://gurdx.cretip.com/en/docs/api-reference/ip-lookup): Looks up any IPv4 or IPv6 address and returns its geography, network owner, timezone, currency and security flags.
- [Bulk IP Lookup](https://gurdx.cretip.com/en/docs/api-reference/ip-bulk): Checks several IP addresses in a single call and returns a full lookup result for each one.
- [IP Reputation](https://gurdx.cretip.com/en/docs/api-reference/ip-reputation): Returns only the threat indicators for an IP address: proxy, VPN, Tor, bot, relay, hosting and blacklist status.
- [ASN Lookup](https://gurdx.cretip.com/en/docs/api-reference/asn): Returns the registry details of an Autonomous System: its owner, contact data, type and announced IP prefixes.
- [BIN Lookup](https://gurdx.cretip.com/en/docs/api-reference/bin): Identifies the issuer, brand, type and country of a payment card from its first digits and tells you whether the BIN is valid.
- [IBAN Lookup](https://gurdx.cretip.com/en/docs/api-reference/iban): Validates an International Bank Account Number and returns its formats and country banking information.
- [Country Lookup](https://gurdx.cretip.com/en/docs/api-reference/country): Returns reference information about a country from its two-letter ISO code.
- [Domain Lookup](https://gurdx.cretip.com/en/docs/api-reference/domain): Checks a domain name for age, mail-authentication records and known danger.
- [Email Scoring](https://gurdx.cretip.com/en/docs/api-reference/email): Scores an email address from 0 to 3 for how likely it is to be fake, disposable or abusive.
- [Phone Validation](https://gurdx.cretip.com/en/docs/api-reference/phone): Validates a phone number for a given country and tells you its carrier and whether it looks real or disposable.
- [Profanity Detection](https://gurdx.cretip.com/en/docs/api-reference/profanity): Scans user-generated text for profanity and abuse and returns a risk score and a safe/unsafe verdict.
- [Payment Fraud Detection](https://gurdx.cretip.com/en/docs/api-reference/payment): Scores a transaction from 0 to 100 for fraud risk by running it through a library of payment-fraud rules.
- [User Data Deletion](https://gurdx.cretip.com/en/docs/api-reference/user-delete): Erases the data Gurdx holds about one of your end users, so you can honor deletion requests under privacy laws.
- [Get IP (Free)](https://gurdx.cretip.com/en/docs/api-reference/free-get-ip): Returns the public IP address of the caller. No API key is needed.
- [Payment Outcome Feedback](https://gurdx.cretip.com/en/docs/api-reference/feedback-payment): Reports what really happened to a payment you scored, so your account's payment model, rule weights and reputation memory learn from it.
- [Fraud Label Feedback](https://gurdx.cretip.com/en/docs/api-reference/feedback-event): Labels an identity (IP, email, email domain, phone, card BIN, customer id, device id or text) as fraud or legitimate, or marks a dashboard event as a true or false positive.
- [Bulk Feedback](https://gurdx.cretip.com/en/docs/api-reference/feedback-bulk): Sends up to 1,000 payment outcomes and labels in one call, for nightly syncs and for backfilling your history.
- [Webhooks](https://gurdx.cretip.com/en/docs/webhooks): Webhooks let Gurdx push a signed JSON message to your server the moment a risky event is detected, so you can react without polling.
- [Integrations overview](https://gurdx.cretip.com/en/docs/integrations/overview): Integrations send short, human-readable alerts from Gurdx to the tools your team already watches, and webhooks connect Gurdx to your own systems.
- [Slack integration](https://gurdx.cretip.com/en/docs/integrations/slack): Send Gurdx alerts to a Slack channel using an incoming webhook, with no code to write.
- [Telegram integration](https://gurdx.cretip.com/en/docs/integrations/telegram): Get Gurdx alerts as Telegram messages in a private chat, group or channel.
- [Discord integration](https://gurdx.cretip.com/en/docs/integrations/discord): Post Gurdx alerts to a Discord channel with a channel webhook.
- [Automation tools](https://gurdx.cretip.com/en/docs/integrations/automation): Connect Gurdx to Zapier, Make, n8n, IFTTT or any no-code tool by pointing a Gurdx webhook at the tool's "catch webhook" trigger.
- [Custom rules](https://gurdx.cretip.com/en/docs/custom-rules): Custom rules let you adjust Gurdx results with your own business logic, such as blacklisting a country or overriding a score, without changing your integration code.
- [Blacklists](https://gurdx.cretip.com/en/docs/blacklists): Blacklists are lists of values you never want to accept, checked automatically on the endpoints that handle that kind of value.
- [Events and alerts](https://gurdx.cretip.com/en/docs/events-and-alerts): An event is the record Gurdx creates whenever an API request produces a risky result, and it is what drives dashboard monitoring, webhooks and chat alerts.
- [Feedback and learning](https://gurdx.cretip.com/en/docs/feedback-and-learning): Tell Gurdx what really happened to the orders and users it scored, and your account's fraud models learn from it every night.
- [Payment fraud prevention](https://gurdx.cretip.com/en/docs/guides/payment-fraud): Score every purchase, deposit or withdrawal before you capture the payment, and route risky ones to review or decline.
- [Reducing chargebacks](https://gurdx.cretip.com/en/docs/guides/chargebacks): Use Gurdx signals before and after an order to reduce disputed payments, and keep evidence that helps when you contest one.
- [Account takeover protection](https://gurdx.cretip.com/en/docs/guides/account-takeover): Spot sign-ins that do not look like the real owner and challenge them before an attacker can empty a wallet or change credentials.
- [Detecting multi-accounting](https://gurdx.cretip.com/en/docs/guides/multi-accounting): Find people who open many accounts to abuse promotions, referral bonuses, free trials or ban evasion.
- [Fake account prevention](https://gurdx.cretip.com/en/docs/guides/fake-accounts): Block bots and throwaway registrations at the front door so your user base, email reputation and support queue stay clean.
- [Content moderation](https://gurdx.cretip.com/en/docs/guides/content-moderation): Filter abusive language in comments, chat, usernames and reviews before it reaches other users.
- [Web personalization](https://gurdx.cretip.com/en/docs/guides/web-personalization): Use the visitor's IP to tailor language, currency, content and compliance behaviour without asking them questions.
- [SMS fraud prevention](https://gurdx.cretip.com/en/docs/guides/sms-fraud): Stop fake and premium-rate numbers from draining your SMS and OTP budget.
- [Changelog](https://gurdx.cretip.com/en/docs/changelog): Release notes for the Gurdx API and platform, newest first.

## OpenAPI Specs

- [openapi](https://gurdx.cretip.com/docs/openapi.json)

## Optional

- [Pricing](https://gurdx.cretip.com/en/pricing)
- [Arabic documentation](https://gurdx.cretip.com/docs)