Live · bubble sort
Step – of –
Getting ready…
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Maths · Science · Code · Class 4 to research and work
Don’t just read the answer. Watch it happen.
Type a question in your own words, paste code, or show a photo of a problem. TellMeHow turns it into a moving picture you can play, pause, rewind and change, one step at a time, from a Class 4 sum to a graduate algorithm or the code you are debugging at work. Wherever it can, a real engine works out the numbers, and anything the AI drew says so.
- Free to use
- No account needed
- Class 4 to research and work
- Works on phones
Ask a question
How it works
Ask. Watch. Control.
Three steps, and you are inside the working instead of reading about it.
- AskType a question in your own words, paste your code, or give input → output examples.
- WatchAn engine works out each step and draws it: bars swap, arrows slide, tables fill, a ball flies.
- ControlPlay, pause, go back a step, jump ahead, repeat a part, and change the numbers to see what happens.
The player: the picture, the code, the values, the explanation and the controls, all following one step number.
What you can ask
Maths, science and code, one player
Tap an example to put it into the question box, then press Visualize. The same box takes a Class 4 sum, a graduate algorithm or a function from work, and biology questions too.
Code
Python, JavaScript, TypeScript, PHP, Java, C, C++, Go or Ruby, run one line at a time: lists, pointers, trees, recursion, tables.
Maths
Sums on a number line, fractions as bars, algebra on a balance, graphs drawn point by point, vectors in 3D.
Physics
Thrown balls, pendulums, springs, slopes, circuits, lenses and charged particles in a field, with the numbers changing as it moves.
Chemistry
Equations balanced atom by atom, molecules you can turn around, gas laws, electron shells, VSEPR shapes and crystal cells.
Who it is for
From Class 4 to the lab and the office
One player, every stage. The depth follows the question you ask, so the same site serves a first sum, a graduate algorithm and the code you work with every day.
School students
Class 4 to Class 12
Sums, fractions, algebra, projectiles and chemical equations, drawn one step at a time. Change the numbers and watch it again, and ask about any step in English, Hindi or Hinglish.
Start with Fraction bars: ½ + ⅓
College and university
Undergraduate and postgraduate courses
Data structures, dynamic programming, graph algorithms, 3D vectors, VSEPR shapes, crystal lattices and a charged particle in a field. Every code entry shows its complexity, and sorting algorithms run side by side.
Start with 0/1 knapsack
Researchers and higher studies
PhD scholars, postgraduates and lab groups
Paste the algorithm from a paper and watch it run on your own data, explore a physical model with the sliders, and turn any step into a PNG for a slide, a poster or a thesis figure. Anything the AI drew is labelled, so you know what to verify.
Start with Charged particle in a magnetic field
Working professionals
Developers, engineers and interview candidates
Trace a function from a pull request line by line, set a breakpoint on a line or a condition, see the same algorithm in another language, and refresh a concept before an interview or a design review.
Start with Dijkstra's shortest paths
Teachers, lecturers and trainers
Classrooms, lecture halls and training rooms
Put a visual on the big screen and step through it at the pace of the room. Quiz me asks the class to predict each step, and a share link opens at exactly the step you want them to replay.
Start with Projectile motion
Parents and self-learners
Helping at home, or learning at your own pace
Open a ready-made visual from the Library, no account needed, and follow the working together. Every step has a short explanation, and going back a step is instant when something did not land the first time.
Start with Long division
Explore the Library
75 ready-made visuals
From adding numbers and fractions to dynamic programming, graph algorithms, 3D vectors, projectiles, crystal structures and molecules. Open one with a click, no account needed.
- DSA · SortingBubble sortNeighbours are compared and swapped until the largest values bubble to the end.O(n²)
- DSA · SearchingBinary searchOn a sorted list, look at the middle and throw away the half that cannot hold the target.O(log n)
- DSA · Data structuresReverse a linked listWalk the list once, turning every arrow around with three pointers: prev, curr and next.O(n)
- DSA · GraphsBreadth-first searchExplore a graph in waves: all neighbours of the start first, then their neighbours, using a queue.O(V + E)
- DSA · Dynamic programming0/1 knapsackPick items with the most value that fit in a bag of capacity W — each item taken at most once.O(n · W)
- Physics · MechanicsProjectile motionA ball launched at 20 m/s and 30°: its path, velocity components, apex and range, with energy bars.
- Maths · Algebra & geometrySolve 2x + 3 = 11A balance scale: the same operation happens on both sides until x stands alone.
- Chemistry · ChemistryBalancing a chemical equationPropane burning: C₃H₈ + O₂ → CO₂ + H₂O, balanced with atom counters on both sides.
Made for learning
Built around how you actually study
Not a video to watch, but a working you can poke at, whether you are in Class 4, in a PhD programme or at work.
One step at a time
Move one step, or jump to the next pass of a loop or the next call. Going back is instant and exact.
Pause where you like
Click a code line to pause there every time, or only when a condition like i == 3 is true.
Try your own values
Change the list, the angle or the resistance. The engine works it out again and keeps your place.
Checked answers
Code the AI writes is tested in your browser before you see it, and labelled if it could not be checked.
Pick up where you left off
Signed in, every question is saved and reopens at the exact step you left.
English, Hindi or Hinglish
Ask about any step and read the explanation in the language you think in.
Works on phones
Big buttons, swipe to step, and the same player on a small screen.
Share a visual
Send a link that opens at the step you chose, to a friend, a colleague, a parent or a whole class.
Where the numbers come from
Worked out, not guessed, and labelled when it isn’t.
You can always tell which kind of answer you are looking at.
- 1Exact
Engines work it out
Arithmetic, algebra, graphs, equation balancing and every code trace are calculated by built-in engines. No AI touches those numbers.
- 2Checked
Models do the maths
Physics and chemistry use hand-built models. The AI only reads your question to pick the model and its inputs; the model does the maths.
- 3Labelled
AI draws the rest
When no engine covers a topic yet, the AI draws the picture from our building blocks and writes its numbers too. It is marked “AI-generated” and has a report button, so check it.
FAQ
Straight answers
The short version of who TellMeHow is for, how it works and what it does with your data. The full list is on the FAQ page.
Is it free?
Yes. Everything on TellMeHow is free, with or without an account. The AI features have a fair daily limit for each person, so the site stays free and available for everyone.
Who is TellMeHow for?
Anyone who wants to see how something works, at any stage. School students from Class 4 use it for sums, fractions, science questions and first programs. College and university students use it for algorithms, data structures, mechanics and chemistry. Postgraduates and researchers use it to watch an algorithm from a paper run on their own data. Working professionals use it to trace real code, prepare for interviews and explain a method to a colleague. Teachers, lecturers and parents use it to show the working on a screen. You do not need to know any coding to start.
Which subjects and languages does it cover?
Maths, physics, chemistry, biology and coding. For code, Python, JavaScript, TypeScript and PHP run inside your own browser; Java, C, C++, Go and Ruby run on a separate code runner when the server has it switched on. Explanations can be written in English, Hindi or Hinglish.
Is AI used?
Only where it helps. Where a built-in engine covers the topic, the numbers are worked out by that engine, not made up by AI. AI reads your question to choose the right engine and inputs, answers “Ask about this step”, and, only when no engine covers a topic, draws the picture and its numbers. Such a picture is marked “AI-generated” and has a report button.
Is my data safe?
Mostly, and here is the honest part. Your history needs an account. A tidied copy of every question the AI answers stays on the server without your name, and a question that three different people ask may be published in the public Library after review. Delete a question on the History page and it leaves your history, though its stored row stays. A photo of a question is read by an outside AI provider and is not stored by TellMeHow. So keep your name and other personal details out of your questions.
Ready? Ask your first question.
No account needed, whatever you are studying, teaching or building. Type it in your own words, paste it, or pick one from the Library.