reCAPTCHA is a service that helps to protect your websites and mobile applications from spam and abuse.
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Last updated 2025-08-28 UTC.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-28 UTC."],[],[],null,["# reCAPTCHA documentation\n=======================\n\n[Read product documentation](/recaptcha/docs/overview)\nreCAPTCHA is a service that helps to protect your websites and mobile applications from spam and abuse.\n[Learn more](/recaptcha/docs/overview)\n[Get started for free](https://console.cloud.google.com/freetrial) \n\n#### Start your proof of concept with $300 in free credit\n\n- Get access to Gemini 2.0 Flash Thinking\n- Free monthly usage of popular products, including AI APIs and BigQuery\n- No automatic charges, no commitment \n[View free product offers](/free/docs/free-cloud-features#free-tier) \n\n#### Keep exploring with 20+ always-free products\n\n\nAccess 20+ free products for common use cases, including AI APIs, VMs, data warehouses,\nand more.\n\nDocumentation resources\n-----------------------\n\nFind quickstarts and guides, review key references, and get help with common issues. \ninfo\n\n### Get started with reCAPTCHA\n\n-\n\n [Overview](/recaptcha/docs/overview)\n\n-\n\n [Versions comparison](/recaptcha/docs/compare-versions)\n\n-\n\n [Test reCAPTCHA in a demo website](/recaptcha/docs/quickstart-app)\n\n-\n\n [Implementation workflow](/recaptcha/docs/implementation-workflow)\n\n-\n\n [Set up reCAPTCHA on websites](/recaptcha/docs/setup-overview-web)\n\n-\n\n [Set up reCAPTCHA on mobile applications](/recaptcha/docs/setup-overview-mobile)\n\n-\n\n [Set up reCAPTCHA at the WAF layer](/recaptcha/docs/setup-overview-waf)\n\n-\n\n [Refine site-specific model](/recaptcha/docs/annotate-assessment)\n\n-\n\n [Migrate from reCAPTCHA Classic](/recaptcha/docs/migrate-recaptcha)\n\nadd_box\n\n### Add additional security\n\n-\n\n [Configure multi-factor authentication](/recaptcha/docs/integrate-account-verification)\n\n-\n\n [Detect password leaks and breached credentials](/recaptcha/docs/check-passwords)\n\n-\n\n [Detect and prevent account-related fraudulent activities](/recaptcha/docs/account-defender)\n\n-\n\n [Detect and prevent account takeovers](/recaptcha/docs/account-takeovers)\n\n-\n\n [Prevent payment fraud](/recaptcha/docs/fraud-prevention)\n\ngroup_work\n\n### Reference and resources\n\n-\n\n [Authentication to reCAPTCHA](/recaptcha/docs/authentication)\n\n-\n\n [Client Libraries](/recaptcha/docs/libraries)\n\n-\n\n [REST API](/recaptcha/docs/reference/rest)\n\n-\n\n [RPC API](/recaptcha/docs/reference/rpc)\n\n-\n\n [Pricing](/recaptcha/pricing)\n\n-\n\n [Billing information](/recaptcha/docs/billing-information)\n\n-\n\n [Quotas and limits](/recaptcha/quotas)\n\n-\n\n [Release notes](/recaptcha/docs/release-notes)\n\n-\n\n [Getting support](/recaptcha/docs/getting-support)\n\n-\n\n [FAQs](/recaptcha/docs/faq)\n\nRelated videos\n--------------"]]
