Generate cryptographic hash (fingerprint) of any file or text. Verify integrity, detect tampering, and ensure data authenticity.
Supports any file type (up to 200 MB recommended). Computes MD5, SHA-1, SHA-256, SHA-384, SHA-512 instantly.
A cryptographic hash function is a mathematical algorithm that maps data of arbitrary size to a fixed-size string of characters (a digest). Even the slightest change in the input produces a completely different output — known as the avalanche effect. Hash functions are fundamental to file integrity verification, digital signatures, password storage, and blockchain technology.
H(file) = digest (MD5: 32 hex chars, SHA-256: 64 hex chars, SHA-512: 128 hex chars)
The probability of two distinct files producing the same hash (collision) is astronomically low for SHA-256, SHA-384, and SHA-512.
The following table shows average computation times for different file sizes on typical devices (Intel i5, 8GB RAM, Chrome/Edge/Firefox). Times may vary based on hardware and browser version.
| File Size | MD5 | SHA-256 | SHA-512 | Recommended |
|---|---|---|---|---|
| 1 MB | < 0.05 sec | < 0.1 sec | < 0.1 sec | ✅ All algorithms work instantly |
| 10 MB | ~0.1 sec | ~0.2 sec | ~0.25 sec | ✅ Suitable for typical files |
| 100 MB | ~0.5 sec | ~1.2 sec | ~1.5 sec | ⚠️ May cause slight delay |
| 500 MB | ~3 sec | ~6 sec | ~7 sec | ❌ Not recommended; use command-line tools |
Message block (512 bits)
│
▼
┌─────────────────────────┐
│ Message Schedule │
│ (Expand to 64 words) │
└─────────────────────────┘
│
▼
Initial hash values (8 x 32-bit) ← Constants (Kt)
│ │
▼ ▼
┌────────────────────────────────────────────────┐
│ for t = 0 to 63: │
│ T1 = h + Σ1(e) + Ch(e,f,g) + Kt + Wt │
│ T2 = Σ0(a) + Maj(a,b,c) │
│ h = g; g = f; f = e; e = d + T1 │
│ d = c; c = b; b = a; a = T1 + T2 │
└────────────────────────────────────────────────┘
│
▼
New hash values → final digest (256 bits)
This iterative compression ensures that each bit of output depends on every bit of input. The functions Σ, Ch, and Maj are bitwise operations that create the avalanche effect.
MD5 (128-bit) – Widely used for checksums but vulnerable to collision attacks since 2004. Not suitable for cryptographic security, though still useful for non-critical integrity checks.
SHA-1 (160-bit) – Deprecated by NIST after 2011 due to theoretical collisions. Avoid for security-sensitive applications.
SHA-256 (256-bit) – Part of the SHA-2 family, currently the industry standard for digital signatures, SSL certificates, and blockchain.
SHA-384 (384-bit) – Truncated version of SHA-512, offers strong security with moderate output size, often used in TLS and cryptographic protocols.
SHA-512 (512-bit) – Offers stronger security margin, recommended for high‑assurance systems and long-term archival integrity.
NIST (National Institute of Standards and Technology) officially recommends SHA-256, SHA-384, or SHA-512 for cryptographic applications. This tool implements all five to support legacy compatibility and modern security standards.
Our tool produces identical results to standard command-line utilities. For example, after computing the SHA‑256 of a file with this tool, you can verify it using:
# Linux / macOS
sha256sum yourfile.txt
# Windows PowerShell
Get-FileHash -Algorithm SHA256 yourfile.txt
This ensures consistency with any other hash verification process.
Open-source projects like Apache, Ubuntu, and PostgreSQL publish SHA-256 or SHA-512 checksums alongside releases. When users download an ISO, they can compute its hash locally and compare — if the hash matches, the file is authentic and uncorrupted. For instance, the Ubuntu 22.04 LTS desktop ISO (approx. 3.8 GB) has a SHA-256 sum published on ubuntu.com. Using this tool, administrators verify that no man-in-the-middle attack or network error altered the image. This practice prevents supply‑chain attacks and ensures software integrity.
Modern hash algorithms like SHA-256 operate via Merkle-Damgård construction: the input message is padded, split into 512‑bit blocks, and processed through a compression function that uses bitwise operations (AND, XOR, rotation) and modular addition. The final output is a 256‑bit state that uniquely represents the original data. Unlike encryption, hashing is one‑way: given a digest, it is computationally infeasible to reconstruct the original message.
shasum or certutil.