Instantly generate secure cryptographic hashes from any text using SHA-256, SHA-512, SHA-1, and more.
How It Works
A Cryptographic Hash Function takes an input (like a string of text or a file) and returns a fixed-size string of bytes, typically represented as a hexadecimal number. This process is deterministic: the same input will always produce the exact same output.
This tool uses your browser's native Web Crypto API to compute the hashes locally on your device. Your data never leaves your browser, ensuring complete privacy.
Why Use Hashes?
- Data Integrity: Hashes are often used to verify that a file or string has not been altered. If even one character of the input changes, the resulting hash will be completely different.
- Password Storage: Systems store hashes of passwords instead of plain text. When you log in, the system hashes your input and compares it to the stored hash.
- Digital Signatures: Used in blockchains, TLS certificates, and software distribution to prove authenticity.
Supported Algorithms
- SHA-256: Part of the SHA-2 family. It is the industry standard for most secure applications, including Bitcoin. It generates a 256-bit (64-character) signature.
- SHA-512: Also part of the SHA-2 family, but operates on 64-bit words and produces a 512-bit (128-character) signature. It's often faster on 64-bit processors.
- SHA-384: A truncated version of SHA-512.
- SHA-1: An older algorithm that produces a 160-bit (40-character) hash. Warning: SHA-1 is cryptographically broken and vulnerable to collision attacks. It should only be used for legacy systems or checksums, not security.
- MD5: A very old algorithm producing a 128-bit (32-character) hash. Extremely vulnerable to collisions and not supported natively by modern Web Crypto standards.
Worked Example
Enter the text hello and choose SHA-256. The generator returns a deterministic 64-character hexadecimal digest. Running the same input again produces the same digest, while changing even one character produces a different value.
Result Interpretation
Compare hashes only when the algorithm and input encoding are identical. A matching digest is evidence that content is unchanged; it is not encryption and cannot prove who created the content.
FAQs
Can a hash be reversed (decrypted)?
No. Cryptographic hash functions are strictly one-way. You cannot derive the original text from the hash. Hackers use "Rainbow Tables" (massive databases of pre-computed hashes) or brute-force to guess the original text.
Is my data sent to a server?
No. All calculations are performed entirely within your browser using JavaScript. No data is transmitted.
Sources & Review
- Secure Hash Standard (FIPS 180-4).
- Last Reviewed: September 2026