Free to start · No card needed
Millions of people are learning and upskilling with AI. Billions have no idea where to start. Cognosc is an AI tutor for anything you ask: it finds the mistake you’re making, teaches you out of it with lessons you can play with, and checks back until it sticks.
YouWhy don’t percentages cancel out?
Good one. First — what do you already know?
A few quick questions, and your course is built around the answers.
Example course · Why percentages don’t cancel out
Or start from one of these
Try it
Most people are. Pick an answer — then watch why.
You put $1,000 into savings that grow 10% a year, and never touch it. Roughly how much is there after 30 years?
How it works
1 · It asks
A few quick questions about the topic — never about yourself. Anything you already know gets skipped.
2 · It teaches
Each lesson is built around what you got wrong, with diagrams you can drag and play with. Stuck? Ask a question right on the page.
3 · It checks back
You explain each idea in your own words. Later, it asks you again — with nothing to look at. That’s how you know you’ve really got it.
Your course
Play one. This example course is on probability that fools almost everyone — two steps are skipped because you already know them. Play with each one, then answer its check; get one wrong and watch what Cognosc does about it.
Step 1 of 3 · Stay or switch?
Pick a door. One has a prize behind it.
So: once the host has opened an empty door, should you switch?
Try getting it wrong on purpose, too — see what happens.
The lessons
Not videos. Not walls of text. Every lesson is written around the idea you got wrong, with diagrams you can grab and move.
Free courses
Free tests
Ten questions, each built on a mistake almost everyone makes. See why after every answer, then get a course that starts from the ones that caught you. No account needed.
Rereading your notes: does it actually work?
10 questions · 4 min
Five heads in a row. Is tails due?
10 questions · 5 min
What causes the Moon’s phases?
10 questions · 4 min
A bat and ball cost $1.10. What does the ball cost?
10 questions · 4 min
Why it sticks
Most of what you learn is gone within days. Cognosc checks in just before you’d forget — one quick question — and each time, the memory lasts longer. Press play and watch the same note, learned two ways.
Learned once
A p-value is how surprising your data would be if nothing were going on — not the chance you’re wrong.
Crystal clear
Learned with Cognosc
A p-value is how surprising your data would be if nothing were going on — not the chance you’re wrong.
Crystal clear
The science
Benjamin Bloom, 1984
Students tutored one-to-one, who had to master each step before the next, did better than 98% of students in a normal class.
Harvard study, 2025
Physics students using a carefully designed AI tutor learned more than twice as much as in a strong active-learning class — in less time.
Research review, 2021
Practising recall spread over days beats cramming it all at once. The typical spaced learner beat 77% of those who crammed.
Pricing
What brings you here?
Pick the one that sounds most like you.
The free-learner fund
Part of every membership goes into a fund for people who can’t pay — students, people between jobs, anyone. We add to it every month too. They get the same Cognosc you do: no ads, no cut-down version, nothing to prove.
Questions
Tap a question and Cognosc answers it.
Ask us anything. A real person reads every email.
Email hello@cognosc.comA chatbot explains things well, then takes your word for it that you understood. Cognosc checks. It knows the common mistakes for each idea before it teaches you, so when you get something wrong it can tell you exactly which mistake you made — and fix that one.
Anything that can be explained and checked: a whole subject, an exam, one topic like Bayes’ theorem or natural selection, or a question you’ve wondered about. It shines where people tend to hold a wrong idea, in maths, statistics, science, economics and the like, because finding that idea is where it starts. It can’t teach a physical skill like playing the guitar, and it teaches from explanations and practice, not from your own textbook.
Yes. Tell it the exam and the topics you’re worried about, and it builds a course for each, starting from what you get wrong. The check-ins keep earlier topics fresh while you move on to new ones. It doesn’t have your exam board’s past papers — bring the topics, it brings the teaching.
Yes. A big subject becomes a series of courses rather than one enormous one, and Cognosc works out what you need first. If something underneath is missing — the percentages under the statistics, say — it plans that in before it goes on.
Then you skip it. Every course starts with a few quick questions about the topic, and anything your answers show you already know is crossed off before the course is built.
Cognosc names the exact mistake — not just “incorrect” — and adds a short lesson written for that mistake, right where you are in the course. You read it, try again, and carry on.
After you explain a step, Cognosc asks you about it again later — one quick question, from memory, with nothing to look at. Each time you get it, the next check-in comes further away. If you like, it emails you when one is due, at most once a week.
Most courses are 30 to 90 minutes of reading, in as many sittings as you like. Check-ins take a minute or two each.
No. It starts from what you already know, skips what you don’t need, and the check-ins do the remembering for you. You just have to be curious.
Lessons are written by AI, so, like any teacher, it can occasionally get something wrong. Each one is built around well-known mistakes in the topic, you can question anything right on the page, and if something looks off, tell us — we fix it.
Yes. Your first course is free — every lesson, diagram and check-in — and so is every course in Free courses. No card, no trial countdown. Membership is $9 a month when you want more courses.
Yes. It’s a website, so there’s nothing to install — it works in any browser, on a phone, tablet or laptop.
When you finish a course you can publish it to Free courses, so anyone can read it — no account needed on their side.
It’s yours. We use it to run your course — never for ads, never sold. You can download everything or delete your account from your account page at any time.
A question, a topic, a subject or an exam — type it, or grab one of these. Your first course is free.