Bold Headless Checkout vs Polar

Bold Headless Checkout has no write-up on Specifiction yet; its figures are above.

Polar is a billing stack for AI products, combining subscriptions, usage billing, credits, invoicing, and merchant-of-record services. It collects usage events into customer meters and adds metered charges to the next invoice. Meters can count, sum, average, find minimums or maximums, and track unique values. Usage collection options cover LLM activity, streaming responses, S3-compatible storage, elapsed time, and manually submitted events; LLM integrations include the Vercel AI SDK and compatible models that return usage data. As merchant of record, Polar says it resells products in over 100 markets and handles payments, sales tax, fraud, refunds, and chargebacks. Its hosted checkout supports localized currencies and includes sales tax. Automated benefits include usage credits, license keys, file downloads up to 10GB, and invitations to private GitHub repositories and Discord. Polar lists apps for iOS and Android and plugins for Raycast and Framer. The Starter plan is free; Pro is $20/month, Growth is $100/month, and Scale is $400/month, with transaction fees on each plan. Usage meters do not block activity when a quota is exceeded; the product using Polar must enforce limits.