Configure RFC 6797 HTTP Strict Transport Security (HSTS) headers, validate max-age durations, includeSubDomains directives, and Chrome/Firefox preload eligibility.

Generate and verify Hash-based Message Authentication Codes (HMAC-SHA256, HMAC-SHA512, HMAC-SHA1) with custom secret keys using Web Crypto API.

Identify the algorithm used to generate a hash. Supports MD5, SHA-1, SHA-256, bcrypt, and more based on length and characters.

Free online file checksum verifier. Calculate and compare SHA-256, SHA-512, and SHA-1 checksums locally in-browser to verify software downloads and data integrity.

Encrypt and decrypt text messages securely in your browser using AES encryption. No data is sent to servers.

Interactive Elliptic Curve Cryptography calculator. Perform point addition, point doubling, scalar multiplication k*G via double-and-add over finite fields and real curves.

Generate DNSSEC Delegation Signer (DS) resource records, calculate SHA-256 and SHA-384 key digests from DNSKEY public keys, and format registrar records.

Generate secure RSA 1024/2048-bit DKIM keypairs and formatted DNS TXT records with automatic multi-string BIND chunking for email authentication.

Simulate the Diffie-Hellman cryptographic key exchange step-by-step. Calculate public keys, shared secret keys, modular exponentiation, and analyze the Discrete Logarithm Problem.

Generate cryptographically secure, high-entropy, memorable passphrases using Diceware methodology directly in your browser.