What is Halfbill?
What Halfbill is, what you can do with it, how paying works, and what you do not need.
Halfbill is a service that gives you access to AI models from Anthropic (the Claude models) and OpenAI (the GPT models). You use the same models the vendors sell, at half their list price. Halfbill is an independent company and is not affiliated with OpenAI or Anthropic.
What you'll need
An email address and a payment card. That is all. You can read this page without either.
What you can do with it
- Chat in your browser. Halfbill Chat is a web chat like the ones you may already know. You type, the model answers. You can switch between Claude and GPT models in the same conversation window. See Use the chat.
- Use AI coding assistants. Tools such as Claude Code and Cursor need an AI "engine" behind them. You can point them at Halfbill instead of the vendor. See Claude Code and Cursor.
- Power your own apps. If you or your team write software, the Halfbill API works with the OpenAI and Anthropic SDKs. That is the developer track: Quick start.
How paying works
You add money to a prepaid balance (we call it credits), and every message you send takes a small amount off that balance, based on how long the message and the answer are. You can also pick a monthly plan for the chat or for coding tools, which gives you a fixed monthly usage allowance. Neither option locks you in. Details: Add credits and Credits or subscription?.
What you do not need
- No OpenAI or Anthropic account. Halfbill is the account.
- No subscription. Prepaid credits are enough. Plans are optional.
- No technical setup for the chat. Sign in and type.
What the words mean
You will meet a few technical words along the way: token, model, API key, base URL. Each one is explained in one or two sentences in the Glossary. You can also read on and come back when a word is unclear.
Want the technical details?
The Overview lists the endpoints, models, and billing rules for developers.
Next step
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