Most study apps charge you for the month whether you open them or not, and almost none will tell you what a single lesson actually costs to produce. Those two facts are related. Here is the whole arithmetic, starting with the part that costs you nothing.
What your free credits actually get you
Everything is priced in credits, and you start with 2,000 of them free. To give that a shape: a full researched course — planning, five parallel researchers, a review pass, and a writer per part — costs roughly 600 to 1,200 credits. An MCQ set or a flashcard deck is 10 to 30. A minute with the voice tutor is 20 to 60. One question about your chapter is 1 to 5. So the free grant comfortably covers a course, a dozen minutes of tutoring, ten practice sets and forty questions, with credits still spare.
You should be able to see exactly what each thing cost you. On most study apps you cannot, and that is a choice somebody made.
So we sell credits, at cost
When you do run out, 1,000 credits is $1, about ৳125 — metered against the AI provider's own list price with no markup added on top. Credits never expire, so a month where you don't study costs you nothing, and there is no card kept on file and nothing recurring to cancel. An empty balance simply means the AI features pause until you decide otherwise.
Why your credits go this far
- Each job runs on the model sized for it — web research on a light tier, lesson writing on the standard tier, the voice tutor on the live model. Flagship-priced models are refused at startup; there is no switch to turn them on.
- Deterministic work is content-addressed and cached. Reopening a lesson, switching modes and coming back, or double-clicking a button costs zero — it never reaches the model twice.
- Research findings for a topic stay reusable, so a topic someone already studied skips the web search entirely.
- Every run has a hard ceiling on model calls, so a confused agent cannot spiral into your balance.
And you can audit it
Every AI call is metered and itemised on your usage page — which chapter, which feature, how many credits. Nothing is bundled into a vague monthly figure, because there is no monthly figure. If you want to show a parent exactly where the money went, you can.
Top up in taka by bKash or a local card through SSLCommerz — no international card and nobody else's card needed. Stripe is there too. Custom amounts start at 100 credits, and inviting a friend gets you 500 credits and them 1,000.