Pricing and Premium access

Pricing

Keep the core product free, then add Premium only when you need the extra study tools.

Signing in stays optional. Signed-in free accounts can still sync the canonical progress snapshot, while Premium adds the bounded saved-study and analytics features on top.

Free core

Learn, browse, and keep progress without a subscription.

The simulation-first product stays available without paywalls across the core concept library, discovery routes, and challenge flows.

Full access to the core interactive concept library

Discovery routes, starter tracks, guided collections, and challenge browsing

Local-first progress, with account sync available after sign-in

Stable concept and section links

Ads may appear only on selected discovery pages

Premium

One bounded layer on top of the free core product.

Saved exact-state setups

Saved compare setups

Exact-state sharing links

Advanced review, analytics, and account-aware study tools

Ad-free browsing on eligible routes

Premium keeps the same learning model, then adds the saved study tools, exact-state sharing, richer review, and ad-free browsing that the current product already supports.

Access model

Signed-out browsing stays free. Local-first progress still works immediately.

Signing in is optional and does not upgrade the account by itself. Free signed-in accounts can sync the same canonical progress snapshot.

Premium adds saved study tools, exact-state sharing, richer review depth, and ad-free browsing.

Ads model

Free browsing may show ads on selected discovery pages only. The live lab, challenge flow, pricing, account, and support surfaces stay clear.

How ads work

Premium billing

Need the public billing policy before opening Stripe? Review Billing / cancellation / refunds

Stripe handles the monthly subscription, billing portal, and bounded entitlement updates. Billing details, cancellation, and refund guidance stay on the billing route.

Billing / cancellation / refunds