With the current digital era, document authenticity and existence verification become increasingly valuable across industries, including legal services, intellectual property protection, and business regulation. Authenticity and existence verification via conventional methods is usually centralized and entity-dependent, which may introduce privacy concerns, points of failure, and extra expenses. This paper presents the design and construction of a decentralized document verification system as an open-source system using blockchain smart contracts to safely register cryptographic proofs of digital material. The solution emphasizes ease, privacy, and usability using just smart contracts without storing actual document information on-chain or off-chain. By allowing users to calculate cryptographic hashes locally and directly interact with the blockchain, the system preserves immutable, transparent, and verifiable records while not compromising on confidentiality.