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UUID & Hash Generator
UUID v1/v4 batch generation, MD5, SHA-1, SHA-256, SHA-512 hash calculation, file drag-and-drop hash verification, 100% client-side, no data uploaded to servers.
UUID v1/v4 batch generation, MD5, SHA-1, SHA-256, SHA-512 hash calculation, file drag-and-drop hash verification, 100% client-side, no data uploaded to servers.
UUID (Universally Unique Identifier) is a 128-bit identifier that is theoretically globally unique, widely used in distributed systems, database primary keys, API tokens, and more. Hash is an algorithm that maps data of arbitrary length to a fixed-length digest, commonly used for data integrity verification, password storage, digital signatures, and more. This tool supports both UUID v1 and v4 batch generation, as well as real-time calculation of MD5, SHA-1, SHA-256, and SHA-512 hash algorithms.
Developers use UUIDs as primary keys in database design to replace auto-increment IDs, avoiding data migration conflicts. In microservice architectures, UUIDs serve as request tracing IDs and message identifiers. During testing, batch UUID generation is used for mock data. After downloading files, SHA-256 verifies file integrity to confirm the file hasn't been tampered with. In cryptographic scenarios, SHA-512 is used for data signature digests. MD5 is commonly used in non-security scenarios for cache key generation and data deduplication.
Switch to the UUID tab, select v4 or v1 version, set the quantity (1-1000), check format options as needed (uppercase, braces, remove hyphens), and click the generate button. Each UUID in the results list has a copy button, or you can copy all at once. Switch to the Hash tab, enter text in the input box, and click Calculate Hash to get results for all four algorithms simultaneously. For file hash calculation, simply drag a file into the dashed area, and the tool will automatically read the file and calculate its hash.
UUID v1 is generated based on the current timestamp and MAC address (or random node identifier), providing time sortability, suitable for scenarios requiring chronological ordering. UUID v4 is entirely random-based, carrying no device or time information, offering better privacy with extremely low collision probability, making it the most commonly used version today.
The collision probability of UUID v4 is extremely low. With 122 bits of randomness out of 128, you'd need to generate approximately 2.7 x 10^14 UUIDs before having a 50% chance of a single collision. Under normal usage scenarios, UUIDs are virtually impossible to duplicate and can be safely used as globally unique identifiers.
MD5 has been proven to have collision vulnerabilities and is not suitable for security scenarios like password storage or digital signatures. However, it can still be used for non-security purposes: file cache keys, data deduplication fingerprints, ETag generation, etc. For security requirements, please use SHA-256 or SHA-512.
SHA-256 is currently the most widely used secure hash algorithm. Application scenarios include: blockchain transaction hashes, SSL/TLS certificate signatures, file integrity verification, password storage (with salt), API request signing, Git commit hashes, and more. It offers the best balance between security and computational performance.
A file hash value is the digital fingerprint of a file; any tiny change will result in a completely different hash. Common uses: verifying file integrity after download to confirm it hasn't been tampered with, comparing whether two files have identical content, detecting file modifications, and cloud storage deduplication. Software publishers typically provide SHA-256 checksums for users to verify.