Scan & Generate
Free Hash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from any text. Everything runs in your browser — nothing is sent to a server.
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Hash Results
What is a Hash?
A cryptographic hash function takes any input and produces a fixed-length string of characters (the "hash" or "digest"). The same input always produces the same hash, but even a tiny change in input produces a completely different output.
Common Hash Algorithms
- MD5 — 128-bit hash (32 hex characters). Fast but no longer considered secure for cryptographic purposes. Still used for checksums and data integrity.
- SHA-1 — 160-bit hash (40 hex characters). Deprecated for security use but still found in legacy systems and Git commit IDs.
- SHA-256 — 256-bit hash (64 hex characters). Part of the SHA-2 family, widely used for data integrity, digital signatures, and blockchain.
- SHA-512 — 512-bit hash (128 hex characters). Provides extra security margin over SHA-256 for sensitive applications.
Use Cases
- File integrity — verify downloads haven't been corrupted or tampered with
- Password storage — store hashes instead of plain-text passwords
- Digital signatures — sign documents and verify authenticity
- Data deduplication — detect duplicate files by comparing hashes
- Blockchain — SHA-256 is the backbone of Bitcoin's proof-of-work
Frequently Asked Questions
What is a hash used for?
A hash turns any input into a fixed-length fingerprint. The same input always produces the same output, and any change to the input produces a completely different one. That makes hashes useful for verifying that a file downloaded intact, that a message was not altered, or that two pieces of data are identical without comparing them directly.
Can a hash be reversed back to the original text?
No. Hashing is one-way by design — the output carries no route back to the input. Short or predictable inputs can still be discovered by hashing likely candidates and comparing, which is why common passwords are easy to look up despite hashing being irreversible.
Which hash algorithm should I use?
For integrity checks and general use, SHA-256. MD5 and SHA-1 are broken for security purposes — practical collision attacks exist for both — and should only be used where you need to match a legacy checksum. Never use a plain hash of any kind to store passwords.
Why is MD5 still around if it is broken?
Because it is fast and still adequate for non-adversarial uses such as spotting accidental file corruption or deduplicating files. It fails only when someone is deliberately trying to construct a collision. Many projects still publish MD5 checksums alongside stronger ones for compatibility.
How do I verify a downloaded file with a hash?
Hash the file you downloaded and compare the result character by character with the checksum published by the source. If they match, the file is byte-identical to the one that was published. If the checksum is hosted on the same server as the file, it proves integrity but not authenticity.
Is my input sent anywhere?
No. Hashing runs entirely in your browser using the Web Crypto API. Nothing you paste is transmitted or stored, which matters because people often hash content they would not want to upload.
What is the difference between hashing and encryption?
Encryption is two-way: with the key you get the original back. Hashing is one-way and has no key — you can only check whether a candidate input produces the same fingerprint. Use encryption to keep something secret, hashing to prove something has not changed.
Should I hash passwords with SHA-256?
No. Password storage needs a deliberately slow algorithm designed for the job — bcrypt, scrypt or Argon2 — with a per-user salt. General-purpose hashes like SHA-256 are built to be fast, which is exactly the wrong property when an attacker is guessing billions of candidates.
Verify Data Integrity with Scan & Generate
The Scan & Generate app can scan QR codes and barcodes containing hash data, with instant copy and share functionality.