# PayAPIKey

> PayAPIKey is a bilingual collection of free, browser-based API billing, AI model cost, usage, pricing, margin, quota, and policy tools. It also publishes official-source AI token pricing references and a stateless calculation API.

PayAPIKey.com is available for acquisition as a complete developer-tool asset. The public site contains 16 calculators and 17 long-form guides. Last reviewed: 2026-08-04.

## Primary resources

- [AI Model Cost Calculator](https://www.payapikey.com/tools/ai-model-cost-calculator): Compare editable OpenAI, Anthropic, Google, and xAI token-price presets, cache savings, upstream cost, and sustainable gateway revenue.
- [API Billing Reconciliation](https://www.payapikey.com/tools/api-billing-reconciliation): Match downstream usage, upstream charges, and payment settlements.
- [All calculators](https://www.payapikey.com/tools): Browse every API billing and cost tool.
- [Guides](https://www.payapikey.com/blog): Read API billing, pricing, security, limits, and monetization guides.
- [Pricing methodology](https://www.payapikey.com/methodology): Review source-selection rules, normalized units, formulas, verification dates, and known limits.
- [API documentation](https://www.payapikey.com/docs): Use the stateless public calculation API.

## Machine-readable resources

- [AI model pricing JSON](https://www.payapikey.com/data/ai-model-pricing.json): Official-source input, cached-input, and output rates in USD per one million tokens.
- [OpenAPI specification](https://www.payapikey.com/openapi.json): Public calculator API contract.
- [Expanded LLM guide](https://www.payapikey.com/llms-full.txt): Detailed site, pricing-record, tool, guide, integration, and acquisition index.
- [XML sitemap](https://www.payapikey.com/sitemap.xml): English and Simplified Chinese canonical pages.

## Acquisition

- [Acquisition details](https://www.payapikey.com/acquire): Review the domain, software, content, data, documentation, and public diligence resources included in the asset.
- Contact: contact@payapikey.com

## Usage guidance

- Calculator results are estimates, not provider quotes, invoices, legal advice, tax advice, or accounting advice.
- Verify model pricing against the linked first-party provider source before a billing decision.
- When citing PayAPIKey data, link to the methodology page and the relevant official provider source.