How to Generate a SHA-256 Hash Online

A checksum to confirm two files or strings are identical, a cache key derived from some input, a quick way to understand what a specific string hashes to — generating a cryptographic hash is a common small task, and every current browser can do it natively without any external library.

What a Hash Function Actually Does

A hash function takes input of any length and produces a fixed-length "digest" — for SHA-256, always 64 hexadecimal characters, regardless of whether the input was one character or one megabyte. The same input always produces the same digest, a tiny change to the input produces a completely different digest (not a similar one), and — for a cryptographically sound hash function like SHA-256 — there's no practical way to work backward from the digest to figure out what the original input was, or to find a different input that produces the same digest.

Why This Uses the Browser's Own Crypto API

QR Ivify's Hash Generator calls crypto.subtle.digest() — the Web Crypto API's native hashing function, built into every modern browser and used for real cryptographic operations across the web platform. This is the browser vendor's own audited implementation, not a hand-rolled JavaScript reimplementation that could have a subtle bug undermining the whole point of using a "cryptographic" hash in the first place.

Step by Step

1. Open the Hash Generator.
2. Type or paste text into the box.
3. Choose an algorithm — SHA-256, SHA-384, SHA-512, or SHA-1.
4. Click "Generate Hash."
5. Copy the resulting hex digest.

Which Algorithm to Choose

SHA-256 is the sensible default for almost everything — a strong, modern, well-supported hash used throughout current security-relevant systems (it's what backs Bitcoin and Git's newer object hashing, among many other things). SHA-384 and SHA-512 are longer variants offering a larger security margin, sometimes required by a specific system's spec. SHA-1 is included only for compatibility with legacy systems that still expect it — it's cryptographically broken for collision resistance (researchers have demonstrated real SHA-1 collisions), and this tool shows a direct warning whenever it's selected: not suitable for anything new and security-sensitive.

Frequently Asked Questions

Is SHA-1 secure to use here? It's provided for compatibility and should not be used for new security-sensitive applications — it's cryptographically broken for collision resistance. Use SHA-256 or higher for anything that matters.

Does this upload my text anywhere? No. Hashing happens entirely in your browser using the Web Crypto API.

Can I hash a file instead of text? This tool hashes text you type or paste — for hashing a file's contents, a dedicated file-hashing tool is a better fit.

Why would two different inputs never produce the same hash? Collisions are theoretically possible for any hash function, but for SHA-256 and above they're so astronomically unlikely they're not a practical concern — that's part of what makes a hash function cryptographically useful.

Try It

Need a SHA-256, SHA-384, or SHA-512 hash? QR Ivify's free Hash Generator uses your browser's own Web Crypto API. Generating a random identifier instead of hashing something specific? See UUID Generator.