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Chat402 Whitepaper

The Chat402 whitepaper provides a comprehensive technical overview of our privacy-first, pay-per-use AI platform built on Solana.

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Download

Download Whitepaper (PDF)

Version 6 - December 2025

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Key Topics Covered

Privacy Model

How Chat402 achieves true privacy through client-side storage and zero server-side data retention.

Payment Mechanism

SPL token delegation for seamless, signless micropayments on Solana.

Game Theory

Economic incentives that align user, operator, and network interests.

Technical Architecture

System design including API gateway, payment verification, and model routing.

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Abstract

Chat402 is a privacy-first LLM API gateway that enables anonymous access to frontier AI models through cryptocurrency micropayments. Unlike traditional AI services that require accounts, collect user data, and sell subscriptions, Chat402 offers:
  • True Privacy: No accounts, no login, no tracking. Conversations stored only in your browser’s localStorage.
  • Pay-Per-Use: No subscriptions. Pay only for tokens consumed, starting at $0.001 per message.
  • Multi-Model Access: GPT-5.2, Claude Opus 4, GPT-4o, Gemini, Grok, DeepSeek - all in one place.
  • Crypto-Native: USDC payments on Solana with sub-second settlement.

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Core Innovation: SPL Token Delegation

Chat402 uses Solana’s SPL token delegation mechanism to enable signless payments:
  1. User approves a one-time delegation of USDC to Chat402’s delegate address
  2. For each prompt, Chat402 automatically transfers the exact cost from user’s wallet
  3. No signature popups - just seamless conversation flow
  4. User can revoke delegation at any time
This approach combines the user experience of subscriptions with the privacy and flexibility of pay-per-use.

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Pricing Model

Chat402 operates on a transparent 2x markup model:
ModelChat402 PriceProvider Cost
GPT-5.2$0.023/1K tokens~$0.012/1K
Claude Opus 4$0.090/1K tokens~$0.045/1K
GPT-4o$0.005/1K tokens~$0.003/1K
DeepSeek Chat$0.001/1K tokens~$0.0005/1K

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Rate Limits

  • Per API Key: 1,000 requests/minute
  • Per IP Address: 200 requests/minute
These limits ensure fair usage while accommodating high-volume applications.
For the complete technical details, security analysis, and implementation specifics, download the full whitepaper.