How Credits Work
What a credit is, what it costs, and what consumes it.
What a Credit Is
A credit is PastpaperLM's internal unit for AI usage. It's pegged to a fixed value.
This peg is what every plan's credit allocation, PAYG package, and per-interaction cost is built on — it doesn't move with daily currency fluctuations.
What Consumes Credits
Every message you send to Epis (the AI tutor) costs credits, and the cost depends on which model answers you:
| Model | Credits per interaction |
|---|---|
| Lite | 4 |
| Bright | 25 |
| Prof | 45 |
Which models you can use at all depends on your plan — see Plans & Pricing.
Lite is available on every plan, including Free. Bright and Prof unlock on paid tiers — this is what makes a Bright/Prof answer meaningfully more expensive than a Lite one, so use Lite for quick questions and save Bright/Prof for the ones that need deeper reasoning.
Where to Go Next
- Plans & Pricing — full comparison of all six tiers
- Daily Limits & Carryover — how your daily cap works, and what happens if you run out
- Topping Up with PAYG Credits — buying extra credits that never expire