Secrets, hashes & encryption
Use Web Crypto with explicit algorithms and local-only inputs. Work stays in your browser tab.
Custom password generator
Generate passwords from your chosen alphabet using unbiased cryptographic randomness.
Secure random token generator
Generate random bytes and format them as hexadecimal or Base64url tokens.
Password composition checker
Inspect length, Unicode characters, repeated runs and character classes locally.
Random password entropy calculator
Calculate entropy for an independently and uniformly random password alphabet.
SHA-384 text hash
Compute the SHA-384 digest of UTF-8 text.
SHA-256 file checksum
Compute a SHA-256 checksum of a local file.
SHA-512 file checksum
Compute a SHA-512 checksum of a local file.
HMAC SHA-512 generator
Authenticate UTF-8 text with an HMAC SHA-512 tag and a local secret.
PBKDF2 key derivation
Derive 256 bits using PBKDF2-HMAC-SHA-256 with an explicit salt and iteration count.
AES-GCM text encryption
Encrypt text with a password using AES-256-GCM, random salt and PBKDF2-SHA-256.
AES-GCM text decryption
Authenticate and decrypt a StillKit encrypted text envelope with its password.
AES-GCM file encryption
Encrypt a local file with a password and download an authenticated StillKit envelope.
AES-GCM file decryption
Authenticate a StillKit encrypted file and download its original bytes as a binary file.