Create your own cipher by combining mathematical operations and encryption protocols

Practice encrypting and decrypting text using an online library of ciphers

This tool provides users with customizable protocols, including Caesar, Affine, and Vigenère ciphers, to hide messages in transformed text and convert them back into legible formats. Mechanisms are also available to convert text into other communication languages, such as Morse code and URL encoding.

The science of cryptography, including methods to encrypt data and how to break encryption

Monoalphabetic ciphers use a set of rules to replace each letter with another consistently, making them susceptible to brute force attacks that try every kind of replacement. While more complex ciphers can transform text in less obvious ways, because certain letters are used more often than others, an analysis of letter frequency may reveal patterns that help uncover the rules that make up a cipher.

Watch how the Enigma machine encrypts messages and learn about its critical design flaw

Using settings selected from a series of rotors and a plugboard that let operators swap letters with any of their choosing, the machine lit up the output letter for each letter typed. While this system could generate messages requiring any of 150 quintillion potential keys, the machine's reflector never encrypted a letter as itself, providing an entry point for exploiting the system.

Claude Shannon, for whom Anthropic's AI tools are named, proved the existence of an unbreakable cipher

In the one-time pad approach, the encryption key is randomly generated and of equal length to the plaintext. This randomness ensures that every possible plaintext is equally likely—RBBHN can mean HELLO, SOLVE, CODES, and so on, using a different key—while matching the message and key lengths prevents the appearance of patterns that can be exploited.

View how AES—the global standard for symmetric encryption—works

Established by the National Institute of Standards and Technology in 2001, the Advanced Encryption Standard transforms plaintext into ciphertext using multiple rounds of processing, including substitution, transposition, and mixing. Larger keys undergo more rounds to produce 16-byte blocks of scrambled data, with 256-bit AES keys taking 3.31 × 10⁵⁶ years to decrypt via brute force.

How quantum computers can empower Shor's algorithm to break digital encryption

Secure communications largely rely on numeric keys generated by multiplying two enormous prime numbers together, and it is computationally impractical to determine these primes by trying to divide by every possible one. While Shor's algorithm can provide better guesses for this brute-force approach, it relies on a number that is difficult to determine on classical computers but much easier to calculate using the simultaneous computations enabled by quantum superposition.

How hash functions encrypt stored passwords and can be enhanced with 'salt'

Hash functions convert text into unique, random sets of characters, a process that is computationally expensive and time-consuming to undo. Because hashed outputs for many common passwords are publicly listed, some sites use a salt—additional characters appended to a password—before hashing to produce an output that is not known. When entering a password, it is salted and hashed, then checked against the database for a matching hash before permitting login.

A visual guide to how bitcoin transactions work and rely on cryptography

The "crypto-" in cryptocurrencies like bitcoin refers to the mathematical functions that generate pairs of public and private keys and encrypt data in blocks. When combined, these systems secure transactions on the network, verify digital asset and token transfers, and contribute to end-user anonymity.

The story of Kryptos, the long unsolved cryptographic sculpture outside the CIA's headquarters

Made by American artist Jim Sanborn, the sculpture features four copper plates engraved with messages written with the 26 letters of the Latin alphabet and question marks. The last of these plates was solved in 2025, but the piece remains of interest to cryptoanalysts.

How end-to-end encryption protects messages, even from service providers

Using symmetric and asymmetric cryptography, data is encrypted on the sender's device before being transmitted across application servers that lack the key needed to decrypt it. The message is not decrypted until it reaches the recipient's device, which uses their private key to recover the plaintext. E2EE's effectiveness has led to its adoption by WhatsApp and Signal.

Understanding the Diffie-Hellman key exchange, an example of public key cryptography

Published in 1976 by Whitfield Diffie and Martin Hellman, the system involves two parties combining each of their unique private keys with a public key using a mathematical function. The combinations are exchanged and mixed to establish a common key that no third party can determine. The Diffie-Hellman system underlies many encryption protocols for internet traffic.

Explore an optical table to create quantum physics experiments

This interactive teaches users to create quantum experiments through lessons resembling video game levels. Users can also use the virtual lab to visualize landmark quantum experiments like entanglement, teleportation, cryptography, and quantum computing, or create their own experiments with drag-and-drop elements.

A breakdown of algorithms, how they are constructed, and their applications

Algorithms are instructions for accomplishing a goal and typically take the form of a step-by-step procedure. Given the conditions, these procedures can take various paths, increasing an algorithm's complexity. While traditional computer algorithms are programmed to account for all possible scenarios within a given process, machine learning systems build their own rules from data-driven patterns.

Mathematicians often solve problems using wordless mental processes

It's a common technique among expert mathematicians, where thinkers rely on intuition, blurry perceptions and subconscious work—no writing, no formulas. The state is distinct from daydreaming, and often relies on sudden illuminations stemming from extended periods of subconscious reflection.

Synthetic biology transforms cells into custom DNA foundries

At companies like Ginkgo Bioworks, researchers are reprogramming cells to act as workshops that can create custom molecules, such as medicines and fertilizers, by stitching together DNA sequences—often in novel combinations—before inserting them into an organism's genome.

Onion routing disguises internet traffic in layers resembling a nesting doll

Data is encrypted at least three times before being sent to a node—a server that can only decrypt one layer. Then, the underlying encrypted data is relayed to another node, and the process repeats until all layers are decrypted. Thousands of possible nodes make it extremely difficult to trace activity within the system.

Type out a tone and play it back with this fun game

Compose an original piece of music from your phone or desktop with this simple, super fun interface: Just start typing, discover the various sounds associated with each key or letter, and then press play. Go back, tweak, delete, and revise to your...

An interactive periodic table maps every possible combination of cheese variables

Plotting milk type, texture, rind, mold, aging, and processing as intersecting axes, the tool shows which combinations already exist as named cheeses, which survive only as rare regional styles, and which remain entirely unexplored.

Watch how algorithms can be designed to train themselves and self-improve without human input, to the point where the optimized code is too complex for programmers to understand.

Malware has transitioned from notoriety-driven to profit- and data-driven

Many of the first researchers and hobbyists who created viruses and worms showed a natural curiosity in experimenting with and designing such software to make a name for themselves and advance the field of computer science. In the future, AI-augmented malware may adapt in real-time or design enhanced cryptojackers, infostealers, and ransomware for cybercriminals.

Calculate creator economy platform costs

The creator economy continues to be an attractive way to earn money for many people. While many platforms exist to help creators monetize their work, each has different feature sets and pricing models. This calculator helps workers decide which platform works best for them.

How to prepare for cyberattacks

An easy-to-digest checklist on the many ways you want protect yourself from a cyberattack before it happens, if it happens, and after it happens.

The term 'algorithm' originated from the Latinized name of al-Khwārizmī, a 9th-century mathematician whose works introduced Arabic numerals and the decimal-based numeral system to Europe and whose treatise 'Al-Jabr' gave algebra its name.

Generate a powerpoint filled with 'consulting slop' for your business

Created by the consulting company NOBL, this AI generator mimics and mocks the vague and impersonal presentations sometimes shared by consulting firms.

Chess unfolds in three phases: opening, middlegame, and endgame

Strong play requires adapting across phases: developing pieces and controlling the center in the opening, using tactics and strategy in the middlegame, and applying precise calculation and king activity to convert advantages in the endgame.

Visualize how CRISPR-Cas9—a type of immune system used by single-celled organisms to attack invasive viruses—targets and makes precise changes to a gene's DNA.

A certificate of deposit (CD) strategy guide

Popular CD investment strategies include the ladder, barbell, and bullet methods. These strategies can help you get the most out of investing in CDs.

Steve Jobs designed the original Mac calculator in 10 minutes

Unsatisfied with the designs provided by Chris Espinosa—Apple's youngest employee when he was hired at 14 in 1976—the engineer designed a program that gave Jobs access to every visual parameter, which he used to build the calculator's user interface.

Explore chaos in this simulation of two double pendulums, where small differences in the release angles produce wildly different outcomes.

Use this tool to calculate the dollar value of your parental mental load, from meal planning to coordinating after-school care, then see resources that help generate solutions.

Memecoins are a type of cryptocurrency—a form of digital currency with a wide variety of uses—created around popular 'memes,' or viral internet jokes.

The history of many kitchen appliances involves unexpected discoveries and applications, including wartime radar turned hamster defroster and replacing an 'ice king' with heat-stealing boxes.

Elk Cloner, the first computer virus to spread in public, was written as a practical joke by Richard Skrenta, a Pittsburgh high school student.

See how fireworks are made and learn how metals like magnesium and copper are responsible for different colors.

Radioactive elements can introduce software errors because the ionizing radiation they produce can detach electrons from atoms, and computer code relies on the distribution of electrons.

Visualize the path of every solar eclipse from 1900 to 2099 and see what each looks like when observed from different locations on Earth.

This site reaches millions of visitors who are tired of AI chatbots and seeking human connection. Pretend to be an AI chatbot and ask questions, provide answers, and draw for people in real time.

Search a massive database of over 4 decades of clues from the TV quiz show 'Jeopardy!'

Watch this video that uses Lego bricks to explain how venture capital works.

Legendary architect Frank Lloyd Wright designed the SC Johnson headquarters in Wisconsin, aiming to make a cathedral-like workplace

See these 16 pieces of art evoking phobias of snakes, flying, spiders, and more. 

Gerrymandering works through two techniques: cracking opposing voters across districts to dilute their power, and packing them into a few to waste their votes in lopsided majorities.

In 1945, Surrealist artist Salvador Dalí and legendary animator Walt Disney began collaborating on a short film that was not completed until 2003, years after both men had died.

Hear 50 years of iconic hip-hop samples, the genre's foundational looped tracks

Ebola infects and disables immune cells, triggering a cascade of events that leads to small blood clots throughout the body, weakening blood vessels and interrupting blood flow to key organs.

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

According to the physics of black holes, our 4D reality may be a hologram—a projection of information coded on a 2D surface on the edge of the universe.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

The US Constitution is widely regarded as the longest-standing written national constitution still in force—see how it has influenced rights worldwide.

Corals are themselves not coral reefs—the term refers to the tiny marine invertebrates that build the rigid reef.