Hash Generator & Checksum Verifier
Generate SHA-256, SHA-512, SHA-384, SHA-1, MD5, and CRC-32 hashes for text or files up to 500 MB. Support for HMAC secret keys, hex/base64 encoding, and instant checksum verification.
Generated Checksums0 algorithms
Hardware-accelerated browser Web Crypto calculation
No hashes generated
Enter text or select a file to compute cryptographic checksums.
Zero-Server Privacy
All text and binary files up to 500 MB are hashed locally in memory using the browser Web Crypto API. No files are ever uploaded.
Simultaneous 6 Algorithms
Computes SHA-256, SHA-512, SHA-384, SHA-1, MD5, and CRC-32 concurrently with hardware-accelerated execution timers.
HMAC Keyed Authentication
Supply a shared secret key to generate Keyed-Hash Message Authentication Codes (HMAC-SHA256, HMAC-SHA512, etc.) for API signing.
Cryptographic Best Practices
SHA-256 for Security
Always prefer SHA-256 or SHA-512 for password verification, cryptographic signatures, and modern file integrity checks.
MD5 & SHA-1 Deprecation
MD5 and SHA-1 have known collision vulnerabilities. Use them only for legacy file checksum matching, not for cryptographic security.
Zero Server Uploads
Even for large 500 MB files, hashing is performed 100% locally on your device via the Web Crypto API. No data is transmitted.
HMAC Authentication
Enable HMAC with a shared secret key to produce message authentication codes that verify both data integrity and origin authenticity.
How it works?
Enter Text or Upload File
Type or paste raw text, or drop any file up to 500 MB into the secure in-browser hash zone.
Instant Web Crypto Hashing
Web Crypto hardware-accelerated algorithms generate SHA-256, SHA-512, SHA-384, SHA-1, MD5, and CRC-32 simultaneously.
Customize & Verify
Toggle lowercase/UPPERCASE or HMAC mode, and paste an expected hash to verify file integrity instantly.
Copy & Export
Copy individual checksums with 1 click or download a formatted `.sha256` / checksum report file.
Frequently Asked Questions
What is a cryptographic hash function?
A cryptographic hash function is a one-way mathematical algorithm that takes an arbitrary block of data and returns a fixed-size bit string (digest). It is computationally infeasible to invert (find the original input) or find two different inputs that produce the identical hash (collision resistance).
Why use SHA-256 instead of MD5 or SHA-1?
MD5 (1991) and SHA-1 (1995) have well-documented mathematical collision attacks where researchers generated different files with identical hashes. SHA-256 (part of SHA-2) remains secure, widely trusted, and is standard for Bitcoin, SSL/TLS, and modern software packages.
What is HMAC and when should I use it?
HMAC (Keyed-Hash Message Authentication Code) combines a cryptographic hash function with a secret key. It verifies both data integrity and data authenticity, ensuring that the message was created by someone possessing the shared secret and has not been altered in transit.
Are my files or sensitive passwords uploaded to any server?
No. Everything runs 100% locally in your browser using the native W3C Web Cryptography API and pure JavaScript. Files never leave your device, and no telemetry or backend requests are made.
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