DEVELOPER

Hash Generator

Calculate cryptographic hashes and checksums for any text or file locally in your browser. Generates SHA-256, SHA-512, SHA-384, SHA-1, and MD5 digests using the native Web Crypto API. No files or strings are ever uploaded to any server.

MD5 and SHA-1 are not secure for passwords.

Both MD5 and SHA-1 suffer from known cryptographic collision vulnerabilities. For password storage, use modern salted key-derivation functions (Argon2, bcrypt, scrypt, or PBKDF2). For cryptographic verification, use SHA-256 or SHA-512.

Uppercase Hex

Generated Cryptographic Hashes

SHA-256 (Recommended)

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SHA-512 (512-bit)

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SHA-384 (384-bit)

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SHA-1 (Legacy / Insecure for Passwords)

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MD5 (128-bit / Legacy Checksum)

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Browser-Native Cryptographic Hashing with Web Crypto

Cryptographic hash functions transform arbitrary data into a fixed-size string of bytes. They are one-way functions designed so that even a single bit change in the input produces an entirely different hash.

Castov uses the native window.crypto.subtle interface, leveraging hardware-accelerated CPU instructions for lightning-fast hash computation without external server dependencies.

File Checksum Verification without Uploading

Verifying download integrity (such as ISO images, software binaries, or database dumps) usually requires command-line utilities like shasum or certutil.

With this tool, you can drop any file into your browser to verify its SHA-256 or MD5 checksum against the provider manifest without uploading a single byte to the web.

How to use this tool

Select Text Input to hash strings, or File Upload to compute checksums for local files.
Enter your text or select a file from your computer.
Toggle between lowercase and uppercase hexadecimal output as required.
Click Copy next to any hash algorithm (SHA-256, SHA-512, MD5) to copy the digest.

Examples

Standard cryptographic digest output examples.

SHA-256 Digest

castov

Hex: 1273934d400199d30c5e7b5fbe92b67faaccd8d63806be44d9f67a57a16f6b5b
Output Length: 256 bits (64 hex characters)

MD5 Checksum (Legacy)

castov

Hex: 765275812e96d92497fbba1409d9491b
Usage: Legacy file integrity verification only

Frequently Asked Questions

Is it safe to compute checksums of confidential files here?

Yes. Files and text strings never leave your machine. The Web Crypto API computes all digests locally in browser memory.

Why are MD5 and SHA-1 marked as insecure for passwords?

Both MD5 and SHA-1 have known collision vulnerabilities where different inputs produce the same hash. For passwords, you should always use salted adaptive algorithms like Argon2, bcrypt, or scrypt.

Which hash algorithm is recommended for general data integrity?

SHA-256 (part of the SHA-2 family) is the industry standard for integrity verification, digital signatures, and blockchain architectures.

Can I hash binary files like images, archives, or binaries?

Yes. Switch to the File Upload tab and choose any file from your disk. The file is read via FileReader into an ArrayBuffer and hashed instantly.

Can I copy the hashes in uppercase format?

Yes. Toggle the Uppercase Hex checkbox to switch all computed hashes between lowercase and uppercase representations.