TL;DR — Quick Summary

lemmeknow identifies unknown strings — hashes, encodings, API keys, UUIDs, credit cards, and more. Paste any text and lemmeknow tells you what it is. Perfect for CTFs and security work.

lemmeknow identifies anything. Hash? Encoding? API key? Paste it — lemmeknow tells you what it is.

Installation

# Cargo
cargo install lemmeknow

Usage

# Identify a hash
lemmeknow "5d41402abc4b2a76b9719d911017c592"
# → MD5

# Identify a JWT
lemmeknow "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..."
# → JSON Web Token

# Identify a UUID
lemmeknow "550e8400-e29b-41d4-a716-446655440000"
# → UUID v4

# From stdin
echo "dGVzdA==" | lemmeknow
# → Base64 Encoded String

# From file
lemmeknow --file unknowns.txt

# JSON output
lemmeknow --json "5d41402abc4b2a76b9719d911017c592"

# Boundy search (find patterns in longer text)
lemmeknow --boundary "The key is 5d41402abc4b2a76b9719d911017c592 here"

Summary

  • lemmeknow identifies 1000+ data patterns instantly
  • Hashes (MD5, SHA), encodings (Base64, JWT), UUIDs, credit cards, API keys
  • Pipe, file, and direct input support
  • JSON output for scripting and automation
  • Essential for CTFs, incident response, and security analysis