OpenAI's flagship AI assistant used by 200M+ people for writing, coding, analysis, and creative work. Offers GPT-4o for fast multimodal tasks and o-series models for reasoning. Best for generalists who want one tool for everything from drafting emails to debugging Python.
Pi
A still-free, uniquely empathetic AI companion surviving in maintenance mode -- lovely for supportive conversation, but a stagnant, at-risk product you shouldn't build a workflow on.
What is Pi?
Pi, from Inflection AI, is an empathy-first 'personal AI' tuned for supportive, natural conversation and voice rather than tasks. It's free with no paid consumer tier (now with some message caps), works across web and mobile, and has a uniquely warm, low-friction tone with eight voices. But after Inflection's founding team left for Microsoft in 2024 and the company pivoted to enterprise, Pi has sat in maintenance mode -- it still runs reliably, but the roadmap is uncertain and the feature set is frozen. It's lovely for companionship, but not something to build a workflow on.
Why we scored it
A still-free, uniquely empathetic AI companion surviving in maintenance mode -- lovely for supportive conversation, but a stagnant, at-risk product you shouldn't build a workflow on.
Pros
- +Genuinely free, no card, no paid upsell
- +Best-in-class empathetic tone and natural voice mode
- +Simple, friction-free UX across web and mobile
- +Real-time web access with multiple voices
- +Rock-solid uptime
Cons
- −Maintenance mode -- founding team gone, roadmap uncertain
- −Not built for productivity, coding, or agentic tasks
- −No API and no developer story
- −Free message caps now apply; feature set frozen
- −Single model, no model choice, weaker than current frontier models
How much does Pi cost?
Free to use, no consumer paid tier as of 2026 (some message/usage caps now apply). No public developer API for the Pi app. As of June 2026.
Best alternatives to Pi.
Same AI chat category, ranked by BigBang Score. Click any to compare side-by-side.
Gemini is Google's flagship AI assistant, built on the multimodal Gemini model family and woven into Search, Workspace, Android, and Chrome. The free tier gives broad access to capable Gemini models, while paid Google AI plans add the strongest reasoning models, higher limits, and large cloud storage. Developers get a first-class API through Google AI Studio and Vertex AI with very large context windows and competitive token pricing. Its deep Google-ecosystem integration and native multimodality make it one of the few genuine co-leaders alongside ChatGPT.
Z.ai is Zhipu AI's chat and developer platform built on the GLM model family (formerly ChatGLM), and one of the fastest-moving labs of 2026. Basic chat on GLM Flash models is free and unlimited, while the flagship GLM-5.x reasoning models -- which rival Opus-class systems on agentic and coding tasks -- come via cheap coding-plan subscriptions (from ~$10/mo) or a very low-cost API. Developers get a strong, English, OpenAI-compatible platform with genuinely free Flash models, not just trial credits. The catch is China jurisdiction and PRC-aligned content rules, plus fast-shifting pricing.
DeepSeek is the Chinese lab that upended AI pricing with frontier-class reasoning and coding models at a fraction of Western costs. Its consumer chat app is free, and the DeepSeek API is among the cheapest anywhere, with an OpenAI-compatible interface and open-weight model releases developers can self-host. Models in its V-series and reasoning line are genuinely strong on math, code, and logic. The trade-off is China jurisdiction and data-governance concerns that matter for Western businesses.
Qwen Chat is Alibaba's free conversational app built on the Qwen model family, one of the most capable open-weight model lines in the world. The consumer app is permanently free with no obvious message caps -- web, mobile, and desktop -- which undercuts every Western rival on price. Developers can call the same models cheaply through Alibaba's DashScope API (OpenAI-compatible), though the always-free dev tier was replaced by a finite trial in 2026. Its main drawbacks are China hosting, a compliance concern for Western firms, and a consumer UX that trails ChatGPT.
Anthropic's AI assistant built around safety and deep reasoning. Handles 200K+ token context windows for analyzing long documents, codebases, and research. Powers Claude Code CLI for agentic development. Best for developers and researchers who need nuanced thinking over quick answers.
Pi - frequently asked.
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