API2D is an OpenAI-compatible API platform for connecting supported apps and SDKs to AI models through a custom endpoint, with request caching and key management.

API2D preview

What API2D does

API2D is an API service for developers and application users who want to connect to AI models through an OpenAI-style interface. The site describes it as a 'fill in your key and use it' experience that reduces setup work for supported apps, websites, and SDKs.

Its core offering is parameter-compatible access to a range of APIs, including OpenAI-style models along with Claude, Stability, vector databases, and Azure TTS. The product also adds server-side features such as caching, knowledge-base and search enhancements, and key management tools for grouped usage or reseller-style distribution.

Core capabilities

OpenAI-compatible API access

Use API2D with software, websites, and SDKs that can point to a custom OpenAI-compatible endpoint. The site positions this as a 'fill in your key and go' workflow.

Broad model and API coverage

The service supports OpenAI's major interfaces as well as Claude, Stability, vector databases, and Azure TTS, based on the site FAQ and product summary.

Request caching

API2D servers cache identical requests for 24 hours. Cached responses do not consume points, and users can opt out with a request header when fresh responses are needed.

Server-side enhancements

The site describes server-side enhancements such as knowledge-base, search, and business plugin APIs, which can be added through ForwardKey and grouped settings.

Key grouping and reseller tools

Users can create and manage keys in groups, assign defaults such as a model, and add built-in search or drawing capabilities. The site also says agent/reseller functionality is available for qualified accounts.

Compatibility guides

API2D includes a compatibility/tutorial area for many popular apps, plus documentation and setup guidance for connecting supported clients.

Common ways to use API2D

  • Use supported AI clients with one endpoint

    Connect an existing chat app, browser plugin, or desktop client that already supports a custom OpenAI base URL, then point it at API2D instead of a direct provider endpoint.

  • Consolidate model access for development

    Build or prototype against OpenAI-style APIs while also reaching other supported services such as Claude or Stability through a single platform.

  • Lower costs on repeated prompts

    Reduce repeat-request spend in high-frequency conversational workflows by relying on API2D's 24-hour caching for identical request bodies.

  • Manage keys for teams or resale

    Set up grouped keys with defaults and add search, drawing, or other server-side enhancements when you need more controlled distribution or team-specific behavior.

  • Onboard a specific app quickly

    Follow the site's compatibility tutorials to configure specific apps and SDKs, especially when you need a documented setup path for a popular client.

Pros and Cons

Pros

  • Works with many OpenAI-compatible apps, websites, and SDKs that accept a custom endpoint.
  • Supports several model families and interfaces beyond OpenAI, including Claude, Stability, vector databases, and Azure TTS.
  • Includes caching that can reduce repeat-request costs.
  • Adds server-side tools such as knowledge-base, search, and grouped key management.
  • Offers multiple payment methods, including local options and Stripe credit cards.

Cons

  • Pricing is not a fixed flat rate; usage is metered in points and the site notes exceptions to the approximate 1.5x reference price.
  • Some capabilities rely on server-side enhancements or specific app support, so compatibility depends on whether the client can set a custom API base URL and follow OpenAI-style requests.

FAQ

What kinds of apps can use API2D?

API2D is intended for software, websites, and SDKs that already support OpenAI-style APIs and allow a custom API base URL or address. The site points users to its compatibility app tutorials after login.

How does API2D charge for usage?

API2D charges by points (P) tied to token usage rather than a fixed monthly fee. The site says pricing is generally about 1.5 times the official provider price, except for the 3.5 yuan recharge tier, and that some requests have a minimum charge of 1P.

What models and interfaces does API2D support?

The site says API2D supports most OpenAI interfaces, Claude, Stability, vector databases, and Azure TTS. It also notes that some requests can benefit from caching and that not every capability is identical to the consumer ChatGPT product because API2D follows API-style interfaces.

What payment methods are supported?

API2D supports WeChat, Alipay, Chinese bank cards, and Stripe credit cards according to the pricing page.

How does caching work?

The site says cached requests are free, cache entries last 24 hours, and users can bypass cache with the `x-api2d-no-cache: 1` request header.

Quick Facts

Category
AI API platform
Primary users
Developers and users of OpenAI-compatible apps
Source domain
api2d.com
Interface style
OpenAI-compatible custom endpoint
Pricing shape
Metered points; approximate 1.5x reference to provider pricing
Key workflow
Register, recharge, and paste a key into a supported app