Free Online Tools

Hash Generator

Generate cryptographic hashes instantly with multiple algorithms

Input Text
SHA-256 Hash

Enter text to generate hash

Quick Examples

What is a Cryptographic Hash?

A cryptographic hash function is a mathematical algorithm that converts an input (or 'message') into a fixed-size string of bytes. The output, called a hash or digest, appears random but is deterministic - the same input will always produce the same hash.

Hash functions are designed to be one-way: it's computationally infeasible to reverse the process and determine the original input from the hash. They're also collision-resistant, meaning it's extremely difficult to find two different inputs that produce the same hash.

Our tool generates hashes using five popular algorithms: MD5 (128-bit), SHA-1 (160-bit), SHA-256 (256-bit), SHA-384 (384-bit), and SHA-512 (512-bit). While MD5 and SHA-1 are deprecated for security purposes, they're still useful for checksums and non-cryptographic applications.

Common Use Cases

Password Storage

Generate secure password hashes for database storage (use SHA-256 or stronger with salt)

Digital Signatures

Create message digests for digital signature verification and authentication

Data Deduplication

Identify duplicate data by comparing hash values instead of full content

Cache Keys

Generate unique cache keys based on content hashes for efficient caching

Hash Algorithms Explained

MD5 (128-bit)

Deprecated

Produces a 32-character hexadecimal hash. While fast and widely used, MD5 is cryptographically broken and should not be used for security purposes. Still useful for checksums and non-security applications.

Length: 32 characters | Use for: Checksums, non-security applications

SHA-1 (160-bit)

Deprecated

Produces a 40-character hexadecimal hash. More secure than MD5 but also cryptographically broken. No longer recommended for security-critical applications.

Length: 40 characters | Use for: Git commits, legacy systems

SHA-256 (256-bit)

Recommended

Produces a 64-character hexadecimal hash. Part of the SHA-2 family, SHA-256 is secure and widely used. Excellent balance of security and performance.

Length: 64 characters | Use for: Password hashing, blockchain, certificates

SHA-384 (384-bit)

Produces a 96-character hexadecimal hash. Stronger variant of SHA-256, provides higher security with slightly more computation.

Length: 96 characters | Use for: High-security applications, certificates

SHA-512 (512-bit)

Most Secure

Produces a 128-character hexadecimal hash. The strongest hash in this collection, provides maximum security at the cost of slightly higher computation.

Length: 128 characters | Use for: Maximum security requirements

Frequently Asked Questions

Can I reverse a hash to get the original text?

No, cryptographic hash functions are designed to be one-way. It's computationally infeasible to reverse a hash to determine the original input. This is a key security feature of hash functions.

Which hash algorithm should I use?

For security purposes, use SHA-256 or stronger (SHA-384, SHA-512). Avoid MD5 and SHA-1 for security-critical applications as they're cryptographically broken. MD5 is fine for checksums and non-security uses.

Why are MD5 and SHA-1 deprecated?

Researchers have found practical collision attacks against both MD5 and SHA-1, meaning it's possible to create two different inputs that produce the same hash. This breaks their security guarantees, making them unsuitable for cryptographic purposes.

Should I use hash for password storage?

For password storage, use specialized password hashing functions like bcrypt, Argon2, or PBKDF2, not simple hash functions. These are designed specifically for passwords and include features like salting and key stretching. Never store passwords as plain MD5 or SHA hashes.

What is a hash collision?

A hash collision occurs when two different inputs produce the same hash output. While theoretically possible due to the pigeonhole principle (infinite inputs mapping to finite outputs), good hash functions make collisions computationally infeasible to find intentionally.

Is my data safe using this tool?

Absolutely! All hashing happens entirely in your browser using JavaScript and the Web Crypto API. No data is sent to our servers or any third party. Your input and generated hashes remain completely private on your device.

Security Warning

Never use simple hash functions alone for password storage! Always use specialized password hashing algorithms like bcrypt or Argon2 with proper salting. Regular hash functions are vulnerable to rainbow table attacks and brute force.