#math

Complexity Explorables

Interactive explorations of complex systems. Emergence, chaos, networks - play with the math.

Khan Academy

Free education for anyone, anywhere. Math, science, computing, and more with personalized learning.

Brilliant

Interactive courses in math, science, and CS. Learn by solving problems, not watching videos.

3Blue1Brown

Grant Sanderson's math animations. Beautiful visualizations that build genuine understanding.

Better Explained

Math and programming concepts explained intuitively. Focus on understanding over memorization.

Intuitive Explanations

Radon Rosborough's blog on math and tech. Documented Replit's legal threats against open source projects.

Art of Problem Solving

Math training for bright students. From contest math to university preparation.

Cut The Knot

Interactive mathematics miscellany. Hundreds of puzzles, proofs, and explorations.

Project Euler

Challenging mathematical/programming problems. 800+ problems requiring code and math.

Quanta Magazine

Science and math journalism. Accessible coverage of cutting-edge research.

tixy.land

Creative code golfing. Write a function to control a 16x16 grid of dots. Minimalist creative coding playground.

Acme Klein Bottles

Cliff Stoll's Klein bottle business. Hand-blown mathematical glass objects and astronomer wisdom.

Falstad

Math and physics applets. Interactive simulations for learning.

arXiv

Preprint server for physics, math, and CS. Where new research appears first.

Wolfram Alpha

Computational knowledge engine. Ask it math, science, or data questions and get computed answers.

MathWorld

Comprehensive mathematics encyclopedia. Definitions, theorems, and explanations for every math concept.

Desmos

Beautiful, powerful graphing calculator in the browser. Free and used in schools worldwide.

OEIS

Online Encyclopedia of Integer Sequences. Look up any sequence of numbers and find its mathematical meaning.