How our
algorithm works
While most study apps don't even keep track of your progress, FourtyFive takes it a massive step further.
Strong recent performance, but retention is fading on chain-rule problems answered >14 days ago.
Absolute
Accuracy
Most revision apps track your performance by the number of questions you answer. FourtyFive builds a living picture.
Not one number.
Three honest ones.
FourtyFive's mastery algorithm does not reduce your ability to a single number. It asks three distinct questions about every topic you study — and combines the answers into a score that reflects what is actually happening in your revision.
How well have you performed?
The algorithm tracks every answer you give, but it does not treat them all equally. Recent attempts matter more than old ones. Hard questions count more than easy ones. And if you answered quickly and accurately, that signals real fluency — not just a lucky guess. As you answer more questions on a topic, older attempts gradually fade in importance.
How much do you actually remember?
Performing well once is not the same as knowing something. The algorithm models how memory works — knowledge fades over time if you do not revisit it. But it does not assume everyone forgets at the same rate. Answer a topic correctly many times with high accuracy, and the memory window grows. Practise once, and the algorithm treats that knowledge as fragile.
How confident should we be?
Answer 30 questions on organic chemistry and the algorithm has a lot of evidence — it's confident in your score. Answer one question on wave optics and it doesn't pretend to know how good you are. Instead, it blends the limited data with your own self-assessment and waits for more evidence before making strong claims.
What runs
after every
answer.
Every time you submit an answer, the algorithm runs through a five-step sequence. The result is a mastery score from 0 to 100 for every topic you have studied. Not an average. Not a guess. A calibrated, evidence-based assessment of where you actually stand.
# scoring · memory · confidence …
→ mastery 0.61 → 0.66
Every answer counts — but not equally
Getting a hard question right after thinking it through shows more than acing an easy one in ten seconds. We weigh how hard the question was, how fast you answered and how recently — so your score reflects how you actually performed, not just a tally of ticks and crosses.
It knows when you're about to forget
Knowledge fades — and different topics fade at different speeds for different students. The algorithm builds a sense of your personal forgetting curve on each topic and pulls it back into your queue just before it starts slipping, not weeks too late.
It earns your trust slowly
With only a few attempts under its belt, the algorithm doesn't pretend to know you yet — it leans on your own confidence rating and stays cautious. The more you practise, the more it trusts the numbers, and the more your score reflects evidence rather than guesswork.
Steady beats a lucky day
A single 90% on a topic doesn't mean you've mastered it. Five 80%s in a row often does. We watch for consistency — because the IB doesn't care about your best day, it cares about your average one. Reliable performance is what moves your score, not flukes.
When you slip, it catches it fast
If your scores suddenly tank on a topic you used to ace, the algorithm doesn't quietly fold that into a long-term average. It treats it as a signal — something's changed — and surfaces the topic immediately for review, before mock week, before exam week, before it costs you marks.
The result?
You study less
(while learning more)
Instead of repeating questions you already know or wasting time on random topics, our algorithm focuses on the questions you're most likely to forget, or that need the most work. It’s like a playlist that adjusts to your performance, helping you lock in what matters most.
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