Hash Generator
Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes
Free Online Hash Generator
Generate cryptographic hashes instantly with our free online hash generator. Enter any text and get MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes all at once. Perfect for developers, security professionals, and anyone needing to verify data integrity or create checksums.
Hash functions are one-way mathematical algorithms that convert input data of any size into a fixed-size string of characters. The same input always produces the same hash, but it's computationally infeasible to reverse the process or find two different inputs with the same hash.
Our generator uses the Web Crypto API for SHA algorithms (providing cryptographically secure results) and a JavaScript implementation for MD5. All processing happens locally in your browser - your data is never transmitted to any server.
Hash Algorithms Comparison
| Algorithm | Output Size | Security | Speed |
|---|---|---|---|
| MD5 | 128 bits (32 hex) | Broken | Fastest |
| SHA-1 | 160 bits (40 hex) | Deprecated | Fast |
| SHA-256 | 256 bits (64 hex) | Secure | Medium |
| SHA-384 | 384 bits (96 hex) | Secure | Medium |
| SHA-512 | 512 bits (128 hex) | Most Secure | Slower |
Common Uses for Hash Functions
File Verification
Compare file hashes to verify downloads haven't been corrupted or tampered with during transfer.
Password Storage
Store password hashes instead of plain text passwords. When users log in, hash their input and compare.
Data Integrity
Detect changes to data by comparing before and after hashes. Any modification changes the hash completely.
Digital Signatures
Hash documents before signing to create efficient, fixed-size signatures regardless of document length.
Blockchain
Cryptocurrencies use SHA-256 for mining and linking blocks together with tamper-evident hashes.
Caching & Deduplication
Use content hashes as unique identifiers to detect duplicate files or cache web resources.
Frequently Asked Questions
Can I reverse a hash to get the original text?
No. Hash functions are one-way. You cannot mathematically reverse a hash. Attackers use rainbow tables or brute force to find inputs that produce known hashes, but this isn't reversing.
Why is MD5 considered broken?
Researchers have found ways to create different inputs that produce the same MD5 hash (collision attacks). This breaks many security applications. MD5 is still fine for checksums but not for security.
Which hash should I use?
For security purposes, use SHA-256 or SHA-512. For password hashing, use specialized algorithms like bcrypt, scrypt, or Argon2, not plain SHA hashes.
Why does a small change completely alter the hash?
This is called the avalanche effect. Good hash functions ensure that changing even one bit of input changes approximately 50% of output bits, making patterns undetectable.
Are these hashes secure for passwords?
Plain hashes are not ideal for passwords because they're fast to compute. Use bcrypt, Argon2, or PBKDF2 which intentionally slow down computation to resist brute force attacks.
What is a salt in password hashing?
A salt is random data added to passwords before hashing. It ensures identical passwords have different hashes and defeats rainbow table attacks. This tool doesn't use salts.