ChatGPT (OpenAI)

🌍 International ✅ Free

ChatGPT is OpenAI's flagship product and the world's most popular AI assistant. Major April 2026 updates: GPT-5.5 released (faster, smarter), Codex cloud coding agent upgraded (plugins/skills, WebSocket acceleration), Workspace Agents (team automation workflows), ChatGPT Images 2.0, OpenAI Privacy Filter (open-weight PII detection). Free tier includes GPT-4o mini and limited GPT-4o access.

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Free tier API pricing No credit card China access Open-source alt Provider alternatives Alternatives

🎁 Free Tier

Daily Limit: Limited requests/day

Model	Context	Limit	Notes
GPT-5.5	`1000k`	`Plus/Pro only`	Released April 2026, smartest model, major upgrade for coding/research/analysis. API $5/M input, $30/M output
GPT-5.5-Cyber	`1000k`	`Trusted Access / enterprise-limited`	GPT-5.5 variant for trusted-access cybersecurity use cases, including security evaluation, vulnerability analysis, and defensive workflows; availability is gated through OpenAI trusted access.
GPT-5.5 Pro	`1050k`	`Pro only`	Deep reasoning variant for complex high-stakes tasks. API $30/M input, $180/M output
GPT-5.4	`128k`	`Plus/Pro`	Previous flagship, still powerful
GPT-4o mini	`128k`	`Rate limited`	Available to free users, fast
GPT-4o	`128k`	`Very limited`	Very limited for free users

🔑 Free API

No free API available

ChatCodingReasoningImagecategory.agent llmchatimagecodingagent

Free API Topic Hubs

AI Opportunity Library What you can build with these free AI tools, how to ship an MVP, and how to monetize. Explore ideas → Free AI API directory Compare DeepSeek, Qwen, Grok, GLM, Hunyuan, Groq, and Cloudflare Workers AI free credits. Open hub → API relay and OpenAI-compatible endpoints Relay options, free models, China-access notes, and SDK-compatible setups. View guide → FreeLLMAPI GitHub guide Open-source free LLM API aggregation, alternatives, and setup notes. Read guide →

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