Are my files uploaded to your server when calculating a hash?

No. Computation happens entirely on your machine using your browser's Web Crypto API and JavaScript. Your file data never leaves your device or touches any server.

What is the difference between SHA-256, MD5, and BLAKE2?

SHA-256 is the NIST cryptographic standard used for digital signatures and blockchain. BLAKE2 is a faster, highly secure modern alternative. MD5 is an older 128-bit algorithm that is cryptographically broken and should only be used for non-security checksum checks.

Why should I verify file checksums?

Verifying a checksum proves that a downloaded software installation file or dataset has not been corrupted during transfer, infected with malware, or modified by a man-in-the-middle attacker.

Client-Side Cryptography

Online Hash Calculator & Checksum Verifier

Compute SHA-256, SHA-512, MD5, SHA-3, and BLAKE2 checksums directly in your browser. 100% private — your files never leave your device.

Drag and drop file here, or click to browse

Client-side only • Maximum file size: 500 MB • Zero server upload

Integrity Verification

How Cryptographic Hashing Protects Your Data

A cryptographic hash function converts arbitrary data into a fixed-size string of characters. Even a 1-bit change in the original file completely alters the resulting hash (known as the avalanche effect). By comparing the hash generated above with the official checksum published by software developers, you can verify that your download has not been corrupted or tampered with.

Supported Hashing Algorithms

Algorithm	Output Bits	Security Level	Primary Use Case
SHA-256	256 bits (64 hex)	Standard / Strong	Software releases, TLS, Bitcoin
SHA-512	512 bits (128 hex)	Maximum / Strong	High-security signatures, OS ISOs
BLAKE2b / BLAKE2s	512 / 256 bits	Modern / Fast	Fast integrity checks, WireGuard
SHA-3 (Keccak)	256 / 512 bits	Next-Gen NIST	Ethereum, modern cryptography
MD5 & SHA-1	128 / 160 bits	Deprecated / Insecure	Legacy checksums (collision risk)

Frequently Asked Questions

Is my file uploaded to any server?

No. The calculator uses the browser's native Web Crypto API and client-side JavaScript. Your file data never leaves your device and is not sent to any remote server.

What is the maximum file size?

The calculator handles files up to 500 MB directly in your browser's RAM without freezing your browser tab.

Need to Send Verified Files to Clients?

Transfer files up to 10 GB with zero-knowledge AES-256-GCM encryption and auto-expiring links.

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