Visualize any algorithm by stepping through your code one statement at a time, forwards or backwards, and watch the call stack, the call tree, every variable, tables and graphs change as it runs.
It runs JavaScript, TypeScript, Lua, Python, Ruby, PHP, Java, Kotlin, Swift, C#, Go, C and C++ in your browser: nothing to install, and your code is never sent anywhere. Examples include bubble sort, binary search, two sum, Fibonacci with memoization, reversing a linked list, breadth-first search and the longest common subsequence.