SecureDevutils

Local Cryptography, Hashing & Decoding

Search and filter our suite of 54 offline, client-side tools.

/
Base64 Encode/Decode
Base64 Encode/Decode
Security

Encode text or files to Base64 and decode Base64 strings

base64encode
JWT Decoder
JWT Decoder
Security

Decode and inspect JSON Web Token header, payload and signature

jwtjson web token
SHA-256 Hasher
SHA-256 Hasher
Security

Calculate cryptographic hashes for text or files without server transmission.

sha256hash
RSA Key Generator
RSA Key Generator
Security

Generate secure RSA public/private key pairs and SSH keys locally.

rsassh
Bcrypt Hasher & Verifier
Bcrypt Hasher & Verifier
Security

Hash passwords and verify text against Bcrypt hashes locally and securely.

bcryptpassword
JWT Expiry Calculator
JWT Expiry Calculator
Security

Calculate token expiration, remaining TTL lifetime, and inspect time claims in RAM.

jwttoken
PEM to JWK Converter
PEM to JWK Converter
Security

Convert RSA/EC PEM public/private keys to RFC 7517 JSON Web Key format client-side.

pemjwk
CORS Header Builder
CORS Header Builder
Web & Frontend

Visual generator and tester for CORS headers with Express, Next.js & Nginx configs.

corsheaders

Local Cryptography, Hashing & Decoding

Security is paramount when developing software. Our suite of security utilities allows you to inspect JWT authentication structures, calculate cryptographic hashes (like SHA-256, SHA-512, MD5), and generate RSA public/private key pairs completely within your browser's local sandbox.

Unlike online tools that upload credentials to remote systems, we utilize the standard Web Crypto API so that private keys and plaintext passwords never cross the network.

Key Features

  • Secure Hash Generator: Calculate MD5, SHA-1, SHA-256, and SHA-512 values locally.
  • JWT Signature Verification: Safely inspect payload signatures and algorithms.
  • RSA Key Generator: Generate secure key pairs in PEM format right in your browser.
  • No Server Logs: Absolute privacy guarantee—no private keys or data are logged.