SHA-256 Hash Generator

Generate SHA-256 (Secure Hash Algorithm 256-bit) cryptographic hashes instantly. Type text for auto-generated hashes or upload files (up to 50MB) for client-side verification—files never leave your device. Perfect for file integrity verification, blockchain development, and data tampering detection.

INPUT TEXT

OR UPLOAD FILE

Max 50MB • PDF, ZIP, TXT, Images, JSON, CSV, Office docs
Files processed locally - never uploaded to server

SHA-256 HASH

Algorithm: SHA-256 (Secure Hash Algorithm 256-bit)

Output Format: 64-digit hexadecimal (256 bits)

What is SHA-256?

SHA-256 (Secure Hash Algorithm 256-bit) is a cryptographic hash function that takes an input of any size and produces a fixed 256-bit (32-byte) hash value, displayed as a 64-character hexadecimal number. It's part of the SHA-2 family designed by the NSA and published by NIST in 2001.

The algorithm is deterministic (same input always produces the same hash), irreversible (you cannot recover the original input from the hash), and collision-resistant (extremely difficult to find two different inputs that produce the same hash). These properties make SHA-256 essential for modern cryptography, blockchain technology, and data integrity verification.

Example:

Input: "Hello World"

SHA-256: a591a6d40bf420404a011733cfb7b190d62c65bf0bcda32b57b277d9ad9f146e

File Hash Verification

Our tool supports client-side file hashing for complete privacy. Upload files up to 50MB (PDF, ZIP, images, documents) and generate SHA-256 checksums instantly—all processing happens in your browser, files are never uploaded to our servers.

✅ Verify Software Downloads

Download software, generate its hash, and compare with the official checksum to ensure authenticity.

🔐 100% Client-Side Processing

Files never leave your device. All hashing is done locally in your browser using Web Crypto API.

Common Use Cases

🔒

File Integrity Verification

Verify downloaded files haven't been corrupted or tampered with by comparing SHA-256 checksums published by software distributors.

🪙

Blockchain & Cryptocurrency

Bitcoin and many cryptocurrencies use SHA-256 for mining proof-of-work and creating transaction identifiers on the blockchain.

✍️

Digital Signatures

Create message digests before signing to ensure authenticity and detect if documents have been altered after signing.

💾

Data Deduplication

Identify duplicate files in storage systems by comparing their SHA-256 hashes instead of byte-by-byte comparison.

Programming with SHA-256

Generate SHA-256 hashes in popular programming languages—copy-paste ready code examples.

JavaScript / Node.js

// Using Web Crypto API (browser)

const hash = await crypto

.subtle.digest('SHA-256',

new TextEncoder().encode(text))

// Returns ArrayBuffer

// Node.js crypto module

const crypto = require('crypto')

const hash = crypto

.createHash('sha256')

.update('text')

.digest('hex')

Python

# Using hashlib module

import hashlib

text = "Hello World"

hash_obj = hashlib.sha256(

text.encode('utf-8')

)

hex_hash = hash_obj.hexdigest()

# Returns 64-char hex string

PHP

// Using hash() function

$text = 'Hello World';

$hash = hash('sha256', $text);

// Returns hex string

// Or use hash_file()

$fileHash = hash_file(

'sha256',

'path/to/file.zip'

);

Java

// Using MessageDigest

import java.security.*;

MessageDigest digest =

MessageDigest.getInstance(

"SHA-256"

);

byte[] hash = digest.digest(

text.getBytes("UTF-8")

);

// Convert to hex string

Frequently Asked Questions

Can SHA-256 hashes be reversed or decrypted?

No. SHA-256 is a one-way cryptographic hash function designed to be irreversible. You cannot recover the original input from the hash. However, if the input is weak (like a common password), attackers can use rainbow tables or brute force to find matches.

Is SHA-256 still secure in 2025?

Yes. SHA-256 remains secure and is widely used in modern cryptographic applications. No practical collision attacks have been demonstrated. It's approved by NIST and used in TLS/SSL, Bitcoin, and government security standards.

Should I use SHA-256 for password storage?

No. While SHA-256 is secure, it's too fast for password hashing, making brute-force attacks feasible. Use specialized password hashing algorithms like bcrypt, Argon2, or PBKDF2 which are intentionally slow to resist brute-force attacks.

What's the difference between SHA-256 and MD5?

SHA-256 produces 256-bit (64 hex char) hashes while MD5 produces 128-bit (32 hex char) hashes. MD5 is cryptographically broken with known collision vulnerabilities and should not be used for security. SHA-256 is much more secure.

How do I verify a file's SHA-256 checksum?

Download the file and generate its SHA-256 hash using this tool or command-line tools (sha256sum on Linux, Get-FileHash on Windows). Compare it with the checksum published by the software distributor. If they match, the file is authentic and uncorrupted.

Why does Bitcoin use SHA-256?

Bitcoin uses SHA-256 in its proof-of-work mining algorithm because it's cryptographically secure, produces consistent results, and is computationally expensive enough to prevent spam while allowing legitimate miners to find valid blocks. The hash output must meet specific difficulty requirements.

Key Properties of SHA-256

🎯

Deterministic

Same input always produces the same 64-character hash

⚡

Fast Computation

Quickly generates hashes for data verification and integrity checks

🔐

One-Way Function

Impossible to reverse the hash to recover original input

🌊

Avalanche Effect

Small input change completely changes the resulting hash

💥

Collision Resistant

Extremely difficult to find two inputs with the same hash

📏

Fixed Length

Always produces 256-bit output regardless of input size

Real-World SHA-256 Hash Examples

Input	SHA-256 Hash (64 hex characters)
"" (empty string)	e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855
Hello World	a591a6d40bf420404a011733cfb7b190d62c65bf0bcda32b57b277d9ad9f146e
hello world (lowercase)	b94d27b9934d3e08a52e52d7da7dabfac484efe37a5380ee9088f7ace2efcde9
The quick brown fox jumps over the lazy dog	d7a8fbb307d7809469ca9abcb0082e4f8d5651e46d3cdb762d02d0bf37c9e592
password123 (weak password)	ef92b778bafe771e89245b89ecbc08a44a4e166c06659911881f383d4473e94f

Notice how even small changes (like capitalization) produce completely different hashes - this is the avalanche effect in action.

Please, do let us know and we'll see what we can do for you.