How credits work

What a credit is

Credits are the single unit that meters AI usage on devlin.ai. Editing simulations by hand, publishing, viewing analytics, and reviewing transcripts are always free. Credits are only spent when the AI runs.

See plans and pricing →

How credits are used

Every AI call (chat turn, evaluation, scenario generation) draws from your credit balance. Here's what each one costs on average, based on real usage from published simulations.

Chat turns

~5 credits per turn on average

Each learner message triggers one AI response. Early turns cost less; later turns cost more because the AI re-reads the full conversation each time to stay in character.

End-of-simulation evaluation

~8 credits per evaluation

When a learner finishes, an AI evaluator grades the conversation against the criteria you defined. Runs once per completion.

AI wizard generation

~50 credits per generation

Describe a scenario in plain English and get a full simulation back in less than a minute. Starting from scratch is free.

Configuration impact

Adds roughly 1 to 2 credits per turn

Longer simulation settings and the “Detailed” response-length setting push per-turn cost up slightly.

Editing simulations by hand, publishing, viewing analytics, and reviewing transcripts are all free. Credits are only used for AI calls.

What a real simulation costs

Credits per completed learner session, including the end-of-sim evaluation. Based on real usage across hundreds of published simulations.

Scenario type
Conversation
Credits per learner

Short training conversation

A focused, single-topic exchange.

~5 turns
~25

Standard roleplayMost common

A fully-fleshed scenario. Most published sims land here.

~10 turns
~50

Long, rich scenario

Multi-part conversations with detailed context.

~15 turns
~100

Real example: Our most-used published simulation is capped at 10 turns and averages ~47 credits per learner completion. At that rate, Core's 35,000 credits/month covers roughly 740 completions of a typical simulation before any top-up is needed.

Credit FAQs

What happens if my learners run out of credits mid-simulation?

Learners never pay. Credits are deducted from your account. If your balance hits zero, new simulations won't start and in-progress ones will return an error message. You'll receive an email alert before this happens (configurable threshold on your Credits page), and you can top up at any time.

Do unused credits roll over or expire?

Monthly subscription credits roll over for up to 3 months before they expire. Annual subscription credits are granted up front and roll over for 12 months before they expire. Top-up credits purchased separately expire 12 months after purchase. Your credit balance always draws from the soonest-to-expire credits first.

Why credits instead of flat monthly pricing?

AI usage costs scale with actual learner activity. Flat pricing either overcharges small deployments or caps usage for large ones. Credits make the costs transparent so you can see exactly what drives spend and forecast it for your rollout.