Heart Rate Calculator could calculate the maximum heart rate and target heart rate base on your gender and age with several scientific calculation methods.

Sequence Diagram Generator is an online tool for creating UML sequence diagrams. It could empowers you to effortlessly create comprehensive sequence diagrams to illustrate how actors and objects interact in a system.

Dot Matrix Text Generator could be used to simulate the effect of LED dot matrix display.

Progress Bar Avatar Generator could add a progress bar to your avatar!

Straddle Checkerboard Cipher is a substitution cipher, except that the substitutions are of variable length. It has formed a component of several impotant field ciphers, the most notable being the VIC cipher used by russian spies during the cold war.

Running Key Cipher is a type of polyalphabetic substitution cipher in which a text, typically from a book, is used to provide a very long keystream.

Simple Substitution Cipher is a cipher that has been in use for many hundreds of years. It basically consists of substituting every plaintext character for a different ciphertext character.

ROT13 Cipher is a simple letter substitution cipher with a specific key where the letters of the alphabet are offset 13 places.

Porta Cipher is a polyalphabetic substitution cipher invented by Giovanni Battista della Porta. Where the Vigenere cipher is a polyalphabetic cipher with 26 alphabets, the Porta is basically the same except it only uses 13 alphabets. The 13 cipher alphabets it uses are reciprocal, so enciphering is the same as deciphering.

Columnar Transposition Cipher is a fairly simple, easy to implement cipher. It is a transposition cipher that follows a simple rule for mixing up the characters in the plaintext to form the ciphertext.

XOR Cipher is a type of additive cipher.

Vernam Cipher (also known as the one-time pad (OTP)) is an encryption technique that cannot be cracked, but requires the use of a one-time pre-shared key the same size as, or longer than, the message being sent.