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Chat402

Pay for AI with Crypto

No subscriptions. No credit cards. Just crypto and control.

The first LLM API gateway built for x402. Access GPT-4, Claude, Gemini, and more with USDC on Solana. Pay-per-prompt.

View Docs
$CHAT402 Contract Address
Coming Soon

Why Chat402?

Built for crypto-native AI applications

💰

Pay-Per-Use

Only pay for what you use. No monthly subscriptions, no commitments. Start with as little as $1 USDC.

⚡

Two Payment Options

Custodial: Deposit USDC once, use signlessly. Non-Custodial: Sign each transaction with your wallet. You choose.

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x402 Protocol

Crypto-native payments powered by HTTP 402. Works with Solana wallets. Pay-per-prompt with transparent costs.

🌐

Multi-Model Access

Access OpenAI, Anthropic, Google, xAI, and DeepSeek models through one unified API.

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Transparent Pricing

Real-time pricing based on actual token usage. No hidden fees, no markups. What you see is what you pay.

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Developer First

Simple REST API, comprehensive docs, and SDKs. Build AI agents, chatbots, and protocols in minutes.

How Payments Work

Choose the payment method that fits your needs

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Custodial Wallet (Recommended)

Deposit USDC to your custodial wallet and chat without signing every transaction. Perfect for high-frequency usage.

  • ✅ One-time deposit
  • ✅ No signatures needed
  • ✅ Instant responses
  • ✅ Best for developers & frequent users
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Non-Custodial (Sign Each TX)

Sign each transaction with your wallet. Maximum security and full control over every payment you make.

  • ✅ Sign every transaction
  • ✅ Full custody of funds
  • ✅ Maximum security
  • ✅ Best for occasional users

Switch anytime: You can use custodial wallets for convenience or non-custodial signing for maximum control. Both work seamlessly with the same API.

Supported Models

Access the best AI models through one API

OpenAI
OpenAI
Anthropic
Anthropic
Google Gemini
Google
xAI Grok
xAI
DeepSeek
DeepSeek

Transparent Pricing

Pay only for actual token usage. No subscriptions, no hidden fees.

GPT-3.5 Turbo
$0.003 / 1K tokens
OpenAI
GPT-4 Turbo
$0.04 / 1K tokens
OpenAI
Claude 4.5 Sonnet
$0.018 / 1K tokens
Anthropic
Gemini 2.5 Flash
$0.0028 / 1K tokens
Google
Grok
$0.0007 / 1K tokens
xAI
DeepSeek Chat
$0.0007 / 1K tokens
DeepSeek

Quick Start

Get up and running in 3 steps

1

Generate API Key

Connect your wallet, custodial wallets are auto-created. Generate an API key on the API Keys page.

2

Fund Your Wallet

Send USDC to your deposit address on Solana. Minimum: $1 USDC.

3

Make Your First Request

Send a POST request to the API or use the web chat interface.

Example cURL Request

curl -X POST https://api.chat402.xyz/api/v1/prompt \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-3.5-turbo",
    "prompt": "Explain blockchain in simple terms"
  }'

Example JavaScript

const response = await fetch('https://api.chat402.xyz/api/v1/prompt', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    model: 'gpt-4',
    prompt: 'Write a haiku about AI'
  })
});

const data = await response.json();
console.log(data.text);