Аңдатпа
This paper proposes a passwordless zero-touch blockchain authentication (ZTBA) system to eliminate dependence on a secret that is stored in the centre by providing high-security usability to various digital services. The architecture leverages decentralized identifiers (DIDs), a smart contract on Ethereum, asymmetric challenge-response signatures, and an AI-backed contextual risk module that evaluates device trust, geolocation consistency and behavior signals on login and recovery operations. A prototype implementation was put to test through controlled attack simulations (replay, man-in-the-middle, phishing-oriented credential stuffing), performance benchmarks, and domain-oriented setups in FinTech, e-commerce and healthcare environments. The experimental results that our proposed model achieved a gain of 40% in reducing authentication falsification risk; suffered no compromise during all phishing/MITM simulated sessions; and has practical response times of 2.8 seconds in FinTech, 3.1 seconds in e-commerce, and 4.5 seconds in healthcare. The system delivered throughput greater than 150 verification transactions per second under concurrent enterprise-style verification loads in an L2 test environment while interoperating with FIDO2, WebAuthn and OAuth 2.0 identity ecosystems The study also assessed DID-linked recovery pathways, which were low-risk and restored account access without reintroducing centralized password-reset weaknesses. The research finds that passwordless authentication, anchored in a blockchain, is capable of offering stronger auditability and resilient trust distribution, as well as improved user experience and a viable foundation for scalable digital identity in Web3 and enterprise infrastructures.