Yes. All hashing uses the browser's native Web Crypto API (for SHA) and runs entirely locally. No data is transmitted.

SHA-256 is recommended for most use cases. Use SHA-512 for extra security. Avoid MD5 and SHA-1 for security-critical applications.

No. Cryptographic hash functions are one-way. You cannot recover the original input from a hash output.

MD5 is no longer considered secure for cryptographic purposes due to known collision vulnerabilities. Use SHA-256 or SHA-512 for security-sensitive applications.

SHA-256 produces a 256-bit hash, while SHA-512 produces a 512-bit hash. SHA-512 can be faster on 64-bit processors.