See algorithms run.
Finally understand them.

Every one of our 89 problems comes with an interactive, step-by-step visualization synced to real code. Stop re-reading solutions you'll forget — watch them work until they click.

89 Problems
17 Topics
176 Code Puzzles
21 Cheatsheets
Bubble Sort
for i in range(n):
  for j in range(n-i-1):
    if arr[j] > arr[j+1]:
      swap(arr, j, j+1)

Don't take our word for it — step through one

This is the core of Algo Mind: watch the algorithm work, one step at a time. Here's bubble sort — see the biggest values bubble to the end. Press play.

Bubble Sort nums = [6, 3, 8, 2, 5]

Bubble sort sweeps left to right, comparing neighbours.

Step 0 / 14

In the app, all 89 problems work like this — with 900+ hand-crafted animation steps across arrays, trees, graphs, stacks, matrices, DP tables, and more.

Built for understanding, not memorizing

Visual walkthroughs to learn the idea, three practice modes to make it stick, and cheatsheets for the night before.

Step-through visualizer

Play, pause, scrub, and change speed through 11 kinds of visualizations — arrays, linked lists, trees, graphs, stacks, matrices, DP tables, sliding windows, backtracking trees, and more.

Code that follows along

Every problem ships with working Python and Kotlin implementations. The exact lines being executed highlight in sync with each visualization step — no guessing how the picture maps to the code.

176 fill-in-the-blank puzzles

Rebuild real solutions by filling in the missing pieces of code, with hints when you're stuck. The fastest way to find out whether you actually understood — or just nodded along.

Practice modes that drill deeper

Re-order the steps of an algorithm, answer true/false checks on the tricky details, pick the right complexity — or mix them all in a quick 5, 10, or 15-problem session.

A real curriculum, not a problem pile

The Core Curriculum walks you through 8 ordered chapters — from Big O foundations to dynamic programming — mixing lessons, cheatsheets, and practice so each idea builds on the last.

Momentum you can see

Daily streaks, XP, a daily challenge, per-topic mastery, and bookmarks for the problems that trip you up. Know exactly what you've mastered and what needs another pass.

21 cheatsheets for the night before

From the Big O Growth Guide to the Binary Search Variation Guide and Monotonic Stacks — 175 sections of curated reference across Fundamentals, Data Structures, and Patterns.

Big O Growth Guide HashMap Patterns Two Pointers Guide Monotonic Stack Top K with Heaps DP Foundations +15 more

17 topics, 89 problems — every one visualized

From your first array scan to backtracking and bit manipulation. Easy, Medium, and Hard problems, all with full explanations, examples, and complexity analysis.

Arrays & Hashing
Two Pointers
Sorting
Math & Geometry
Dynamic Programming
Greedy
Binary Search
Heap / Priority Queue
Sliding Window
Graphs
Stack
Backtracking
Bit Manipulation
Linked List
Trees
Tries
Intervals

Start free. Upgrade when it's working for you.

No credit card needed to start learning. Premium unlocks the full library when you're ready to go deeper.

Free

Learn the fundamentals, build the habit.

  • Start the Core Curriculum and unlock topics as you solve
  • Interactive visualizations on every problem you open
  • Starter cheatsheets
  • Streaks, XP, and progress tracking
Download free

Your next interview won't wait

Reading solutions feels like progress. Understanding them is progress. Download Algo Mind and step through your first algorithm in the next five minutes.

GET IT ON Google Play Coming soon DOWNLOAD ON THE App Store

Common questions

Everything you need to know before getting started.

Is it free?

Free to download and free to start learning — no credit card required. You can work through the early curriculum and unlock more topics as you solve. Premium unlocks the full library (all 17 topics, 89 walkthroughs, 176 puzzles, and 21 cheatsheets) and comes with a 7-day free trial you can cancel anytime.

How is this different from LeetCode?

LeetCode tests whether you can solve a problem. Algo Mind teaches you to understand it. Every problem here has an interactive visualization that shows what the algorithm does at each step, with the matching code lines highlighted in sync. Then practice modes — step sequencing, true/false checks, and fill-in-the-blank code puzzles — verify the understanding actually stuck.

What if I'm a complete beginner?

That's exactly who the Core Curriculum is for. It starts with Big O and recursion fundamentals, then builds chapter by chapter through arrays, two pointers, stacks, binary search, sliding window, linked lists, trees, and into sorting and dynamic programming. Each idea builds on the previous one.

What languages are supported?

Every problem includes complete, syntax-highlighted implementations in Python and Kotlin, both synced line-by-line with the visualizations. More languages are planned.

Is it on iOS?

Android is available now on Google Play. The iOS version is built on the same codebase and is coming to the App Store soon.