Updated September 28, 2026
What is Fee model?
In short
The shape of a provider's charges: per use, on a subscription, against a prepaid balance, or free software you host.
A fee model is the shape of the charge before any number appears: usage-based, subscription, prepaid balance, or self-hosted. The shape decides who carries the risk, since a prepaid balance sits with the provider while a monthly fee fixes your cost up front. Apache APISIX AI Gateway is Free (Apache 2.0 open source, self-hosted) and Aptible is $200/month base fee for LLM Gateway plus token usage. AI/ML API bills per model against a prepaid balance with a minimum top-up, Arize AI runs a freemium subscription with free, paid and custom tiers, and 4everland charges pay-as-you-go in its own token alongside free Trial and Standard plans.
Sources
- aimlapi.com, checked September 26, 2026
- apisix.apache.org, checked September 26, 2026
- arize.com, checked September 26, 2026
- docs.4everland.org, checked September 26, 2026
- aptible.com, checked September 26, 2026