Hash Generator — SHA-256, SHA-512, SHA-1, No Upload Required
Generate SHA-256, SHA-512, SHA-1, or SHA-384 hashes using the browser's native Web Crypto API — no library, no upload, no server. Paste text and get the hash instantly. Nothing leaves your device.
How to use this tool
- Paste text or drop a file to hash.
- Select the hash algorithm (SHA-256, SHA-512, MD5, etc.).
- Copy the generated hash.
About Hash Generator
A cryptographic hash function takes input of any length and produces a fixed-size string of bytes — the digest — in a way that is deterministic and one-way. The same input always yields the same digest, but you cannot work backward from a digest to the original input, and even a single-character change to the input produces a completely different output (the avalanche effect). Hashes are the workhorse behind file integrity checks, content fingerprinting, deduplication, digital signatures, and verifying that two pieces of data are identical without comparing them byte by byte.
This tool supports SHA-256, SHA-512, SHA-1, and SHA-384 via the browser's native Web Crypto API. SHA-256 and SHA-512 are members of the SHA-2 family and are the modern default for new work; SHA-256 outputs a 64-character hex digest and is what most checksum and signing systems use today. SHA-1 and the older MD5 are included in many tools for compatibility, but both are cryptographically broken — practical collision attacks exist — so they must never be used for security purposes, only for non-adversarial tasks like matching against a legacy checksum. MD5 is not offered here because the Web Crypto API does not implement it.
The most important thing to understand is that hashing is not encryption. Encryption is reversible with a key, so you can recover the original; hashing is intentionally irreversible, with no key and no way back. That is exactly why hashes are used to store and check passwords without keeping the password itself. But a raw hash of a password is weak: identical passwords produce identical hashes, and attackers precompute huge lookup tables (rainbow tables) of common passwords. The fix is salting — adding a unique random value to each password before hashing so identical passwords get different digests and precomputed tables are useless.
For password storage specifically, even salted SHA-256 is the wrong tool, because fast hashes let an attacker try billions of guesses per second on stolen data. Purpose-built, deliberately slow algorithms like bcrypt, scrypt, or Argon2 are the correct choice there. Use the hashes here for what they are good at: verifying a download matches a publisher's checksum, fingerprinting content for caching or deduplication, or generating an integrity value. Everything is computed locally in your browser, so the text you hash is never transmitted.
Frequently Asked Questions
- Which hash algorithms does this tool support?
- SHA-256, SHA-512, SHA-1, and SHA-384, all computed with the browser's native Web Crypto API without any external library. SHA-256 is the sensible default for checksums and integrity work; the longer SHA-512 and SHA-384 are useful where a larger digest is required.
- Why is MD5 not available?
- The Web Crypto API that this tool relies on does not implement MD5, so it is not offered. That is no real loss, because MD5 is cryptographically broken — collisions can be produced trivially — and SHA-256 is the appropriate modern replacement for nearly every use case where MD5 once appeared.
- Is hashing the same as encryption?
- No. Encryption is reversible: with the right key you can recover the original data. Hashing is one-way by design — there is no key and no way to reconstruct the input from the digest. That irreversibility is exactly why hashes are used for integrity checks and password verification rather than for keeping data confidential.
- Can I use these hashes to store passwords?
- Not directly. General-purpose hashes like SHA-256 are fast, which lets attackers test billions of guesses per second against stolen data. Password storage needs a deliberately slow, salted algorithm such as bcrypt, scrypt, or Argon2. Use these SHA hashes for checksums and fingerprinting, not for protecting credentials.
- What is salting and why does it matter?
- A salt is a unique random value added to each input before hashing. Without it, identical passwords produce identical hashes and attackers can match them against precomputed rainbow tables. A unique salt per password makes those tables useless and ensures two users with the same password still get different stored hashes.
- Why is SHA-1 considered unsafe?
- Researchers have demonstrated practical collision attacks against SHA-1, meaning two different inputs can be made to share a digest. That breaks the guarantee a hash is supposed to provide, so SHA-1 must not be used for signatures or any security decision. It remains here only for compatibility with legacy systems that still emit it.
- Is my text uploaded anywhere when I hash it?
- No. The hash is computed entirely in your browser through the Web Crypto API. Nothing you enter is sent to a server or logged, so you can safely hash content you would not want to leave your device.
- Will the same text always produce the same hash?
- Yes. Hash functions are deterministic, so identical input always yields an identical digest with a given algorithm. Conversely, changing even one character produces a completely different-looking hash, which is what makes hashing reliable for detecting whether data has been altered.
Embed this tool on your site
Free. One line of HTML — the tool runs in your visitor's browser, no data sent to anyone.
<iframe src="https://brevio.pro/embed/hash-generator" width="100%" height="600" loading="lazy" style="border:1px solid #e5e5e5;border-radius:8px" title="Hash Generator — brevio"></iframe> <p style="font:12px/1.4 sans-serif"><a href="https://brevio.pro/tools/hash-generator">Hash Generator</a> by <a href="https://brevio.pro">brevio</a></p>