Free Online Hash Generator

Our hash generator creates cryptographic hash values for any text using five widely-used algorithms: MD5, SHA-1, SHA-256, SHA-384, and SHA-512. All hashing runs entirely in your browser using the Web Crypto API — your input never leaves your device. Click any hash to copy it to your clipboard, and use the compare feature to verify hashes against known values.

What Is a Hash Function?

A cryptographic hash function takes any input — a word, a paragraph, or an entire file — and produces a fixed-length string of characters called a hash, digest, or checksum. The same input always produces the same hash, but even a tiny change in the input produces a completely different output. This property is called the avalanche effect.

Hash functions are one-way: you can easily compute the hash from an input, but it is computationally infeasible to reverse the process and recover the original input from the hash. This makes them essential for password storage, data integrity verification, digital signatures, and many security protocols.

Hash Algorithms Explained

MD5 (Message Digest 5) produces a 128-bit (32-character hex) hash. It was widely used for checksums and file verification but is now considered cryptographically broken due to collision vulnerabilities discovered in 2004. MD5 should not be used for security purposes but remains useful for non-security checksums and legacy compatibility.

SHA-1 (Secure Hash Algorithm 1) produces a 160-bit (40-character hex) hash. Like MD5, it has been deprecated for security use after practical collision attacks were demonstrated in 2017. Most certificate authorities and browsers no longer accept SHA-1 signatures.

SHA-256 is part of the SHA-2 family and produces a 256-bit (64-character hex) hash. It is the current industry standard for most security applications including SSL/TLS certificates, Bitcoin mining, code signing, and password hashing. SHA-256 has no known practical vulnerabilities.

SHA-384 produces a 384-bit (96-character hex) hash and provides a higher security margin than SHA-256. It is commonly used in government and military applications where extra security assurance is required.

SHA-512 produces a 512-bit (128-character hex) hash and offers the highest security level in the SHA-2 family. It performs well on 64-bit systems and is used in high-security applications, some cryptocurrency implementations, and secure file verification.

Common Uses for Hash Generators

Verifying file integrity — software downloads often include an SHA-256 hash. After downloading, you can hash the file locally and compare it to the published hash to confirm the file wasn't corrupted or tampered with during download.

Password storage — responsible applications never store passwords in plain text. Instead, they store the hash of the password. When you log in, the system hashes your input and compares it to the stored hash. Note that modern password storage uses specialized algorithms like bcrypt or Argon2 with salting, not plain SHA-256.

Data deduplication — by hashing files or data blocks, systems can quickly identify duplicates without comparing the actual content byte-by-byte.

Digital signatures and certificates — SSL/TLS certificates use SHA-256 hashes as part of the digital signature process that verifies the authenticity of websites and software.

Frequently Asked Questions

Can a hash be reversed back to the original text?

No. Cryptographic hash functions are designed to be one-way. You cannot mathematically reverse a hash to recover the input. However, short or common inputs can sometimes be found using rainbow tables or brute-force attacks, which is why passwords should always be long and complex.

Why do MD5 and SHA-1 say "not secure"?

Researchers have demonstrated practical collision attacks against both MD5 and SHA-1, meaning it is possible to create two different inputs that produce the same hash. For security applications like digital signatures and certificates, this is a critical flaw. However, both are still fine for non-security purposes like file checksums.

Which hash algorithm should I use?

For most purposes, SHA-256 is the recommended choice. It is the current industry standard, widely supported, and has no known vulnerabilities. Use SHA-512 if you need extra security margin or are working on a 64-bit optimized system.

Is my text stored or sent anywhere?

No. All hashing is performed entirely in your browser using the Web Crypto API for SHA algorithms and a client-side JavaScript implementation for MD5. Your text never leaves your device.

Can I hash files with this tool?

This tool hashes text input. For hashing files, you would need a file-based hash tool. The underlying algorithms are identical — the tool would read the file as bytes and pass them through the same hash function.