Crypto & Security Tools

These tools cover the cryptographic and account-security work that comes up constantly but rarely deserves installing a dedicated app for: hashing text with MD5 or SHA-256, generating and verifying Bcrypt hashes for password storage, producing TOTP codes to test two-factor login flows, and checking how strong a password actually is against real cracking-time estimates rather than a simplistic "add a number and a symbol" rule. The RSA Key Pair and HMAC generators exist for developers setting up signing or encryption who need a quick key pair or signature without spinning up OpenSSL. BIP39 Mnemonic Generator is specifically for anyone working with crypto wallets who needs to understand or test how a seed phrase maps to a wallet address — and the Ethereum Unit Converter and Gas Fee Calculator solve the unglamorous but constant problem of moving between Wei, Gwei and Ether without losing precision, using BigInt internally instead of floating-point math that would silently round incorrectly at these magnitudes.

The common thread across this category is that the input is often sensitive by nature — a real password, a seed phrase, a private token — so everything runs locally in your browser with no network request involved, which matters more here than almost anywhere else on the site.