Our team runs into this during security configuration checks: uploading sensitive text to third-party services is uncomfortable. BIP39 Mnemonic Generator keeps the bip39 generator flow short, and CSPRNG helps with pre-handoff review for repeated Full-stack Developer work.
crypto.getRandomValues + SHA-256 — nothing leaves your browser. Use this only for testing or learning, NEVER for storing real funds. For production wallets, generate phrases offline on a hardware wallet (Ledger, Trezor) or air-gapped device.