Buy in the App Store or Google Play. Prices below are for the U.S. storefront; your store shows local pricing before purchase.
A top-up that arrives on its own, every month.
U.S. storefront price: US$3.99 per month. Renews automatically until cancelled. This website does not take payment.
One purchase. No auto-renewal.
U.S. storefront price: one payment of US$5.99 with no renewal. This website does not take payment.
UnimeType prices work in credits rather than dollars, because that is what you are actually buying. A conversion costs one credit. Polish and Explain return much longer text, so they cost more.
The multiplier for a model is shown when you pick it, never after the fact. Both products spend from the same balance.