All the best of AI chat all in one app

ChatGPT is built for anything. ZeroTwo is built for everything.

TL;DR: AI chat is a conversational interface to a large language model. The best AI chat is the one that doesn't lock you into a single model — ZeroTwo gives you GPT-5, Claude Opus 4.6, Gemini 2.5 Pro, Grok 4, and 56 more models in one chat. Free tier — no credit card required.

60+

AI models in one chat

thread, every model

answers side-by-side

credit card to start

What is AI chat?

AI chat is a conversational interface to a large language model. You type in natural language; the model responds with text, code, citations, structured analysis, or media. Modern AI chat wraps one or more LLMs with file upload, web search, image generation, and persistent memory — turning a raw model into a working assistant.

Independent research published by NBER (Brynjolfsson, Li, Raymond, 2023) measured a 14% productivity gain across 5,179 customer-support agents using generative AI chat, with the largest gains for novice workers. A 2023 Science study from MIT found AI chat cut professional writing time by 40% while raising output quality scores by 18%. The pattern is consistent across legal, financial, and software-engineering domains.

The catch: each model has different strengths. LMSYS Chatbot Arena — the standard human-preference benchmark — shows different leaders for reasoning, coding, multilingual tasks, and long-context work. Locking yourself into one provider means accepting the model's worst categories along with its best.

Why ZeroTwo is the AI chat people stay in

One window. Every model. Every modality. Built to replace the tab-switching tax of running ChatGPT, Claude, and Gemini in parallel.

Every frontier model — one chat window

Switch between GPT-5, Claude Opus 4.6, Gemini 2.5 Pro, Grok 4, and Perplexity Sonar mid-conversation. The thread, files, and context follow you across providers.

See the model library →

Side-by-side compare

Send one prompt to two models at once. Pick the better answer in 5 seconds instead of guessing.

Cited web search

Sonar, Gemini Grounding, and OpenAI browse return real URLs you can verify — not hallucinated sources.

How web search works →

Image, video, voice — same chat

Generate with FLUX, Imagen 4, GPT Image, and Veo without leaving the conversation.

Image generation →

Drop in PDFs, sheets, and decks

Up to 100MB per file. Models read structured tables, citations stay anchored to source pages, and Canvas lets you edit the document inline.

Try Canvas →

Stop picking your AI. Use them all.

Open one chat window. Send the same prompt to GPT-5 and Claude Opus 4.6. Ship the better answer.

Try free vs ChatGPT

Need to move beyond a single-model chat? See the ZeroTwo AI workspace workflow.

AI chat compared: ZeroTwo vs ChatGPT vs Claude vs Gemini

Same task, four different products. Specs as of May 2026.

Capability	ZeroTwo	ChatGPT Plus	Claude Pro	Gemini Advanced
Models you can chat with	60+ from OpenAI, Anthropic, Google, xAI, Meta, Mistral, DeepSeek	OpenAI only	Anthropic only	Google only
Side-by-side comparison
Cited web search		Bing-only	Limited
Native image generation	FLUX, Imagen 4, GPT Image	GPT Image		Imagen
Native video generation	Veo + Sora-class models	Sora (limited)		Veo
PDF / spreadsheet upload
Free tier with frontier models		GPT-5 limited	Sonnet limited
Monthly price for everything	$29.99	$20 (one model family)	$20	$20

Sources: provider pricing pages, LMSYS Arena, Artificial Analysis. Verified May 2026.

How to pick the right AI chat model for the task

Direct answer: match the model to the task category. Use this decision framework.

If your task is…	Start with	Why
Long-form writing or editing	Claude Opus 4.6	Highest preference scores on creative writing in Arena
Code generation + review	GPT-5 or Claude	Tied lead on SWE-Bench Verified
Multimodal (PDFs, images, video)	Gemini 2.5 Pro	Native million-token multimodal context
Real-time / breaking news	Grok 4 or Sonar	Live X/web indexing
Cited research	Perplexity Sonar	Inline citations to verifiable sources
Anything where the answer matters	Two models, side-by-side	Reduces hallucination risk via cross-check

As Anthropic's research team noted in a 2024 paper on model comparison: "No single language model dominates across all task categories. Practitioners benefit from model-routing or side-by-side workflows." ZeroTwo is the easiest way to put that into practice without paying for three subscriptions.

Frequently asked questions

What is AI chat?+

AI chat is a conversational interface that lets you talk to a large language model in natural language and get back text, code, citations, images, or analysis. Modern AI chat apps wrap one or more LLMs (GPT-5, Claude, Gemini, Grok, etc.) with file upload, web search, and memory. ZeroTwo is multi-model AI chat — every frontier model is available in one window, with a free tier so you can start without a credit card.

Is ZeroTwo AI chat free?+

Yes. ZeroTwo has a free tier with daily messages across many models — popular frontier models included with rate limits. No credit card required to start. ZeroTwo Pro removes the daily limits and unlocks unlimited image/video generation, deep research, and team collaboration.

Which AI chat model is best?+

There is no single 'best' AI chat model — each frontier model wins in different domains. Independent benchmarks like LMSYS Chatbot Arena show GPT-5 leads on general reasoning, Claude Opus 4.6 leads on long-form writing and code review, Gemini 2.5 Pro leads on multimodal tasks, and Grok 4 leads on real-time information. The advantage of ZeroTwo is you do not have to pick — send the same prompt to two models side-by-side and use whichever answer wins.

Can I use AI chat without signing up?+

ZeroTwo lets you start chatting immediately with a guest session — no signup wall. To save chat history, sync across devices, or upload files, create a free account. Most single-provider chatbots (ChatGPT, Claude, Gemini) now require a login for any model beyond a basic tier.

How is ZeroTwo different from ChatGPT?+

ChatGPT is a chat interface for OpenAI's models. ZeroTwo is a chat interface for every major model — including OpenAI's. It replaces ChatGPT Plus, Claude Pro, and Gemini Advanced (which most users stack separately) and adds side-by-side comparison, multi-engine image/video generation, and a unified file workspace.

Does AI chat work on mobile?+

Yes. ZeroTwo runs in any modern browser and ships native iOS and Android apps, so you can continue a chat from desktop on your phone. Files, images, and voice input sync across devices.

Is my AI chat data private?+

Yes. ZeroTwo encrypts conversations in transit and at rest, never trains models on your prompts, and supports team workspaces with role-based access. You can delete any conversation permanently from settings. See the privacy page for the full data-handling policy.

What can I do with AI chat that I can't do with Google?+

Google returns links; AI chat returns synthesis. With AI chat you can ask compound questions ('summarize this 80-page contract and flag clauses that conflict with California law'), iterate ('make it shorter, then translate to Spanish'), and feed it your own files. A 2024 Stanford study found knowledge workers complete writing-intensive tasks 37% faster with AI chat than with traditional search.

Key takeaways

AI chat lets you talk to a frontier LLM in natural language and get text, code, citations, or media back in one thread.
Single-provider apps lock you into one model family. Multi-model AI chat lets you pick the best answer per task.
ZeroTwo packs 60+ models — including GPT-5, Claude Opus 4.6, Gemini 2.5 Pro, Grok 4 — into one chat workspace.
Side-by-side comparison turns model selection from a guess into a verifiable test.
Free tier with no credit card means you can validate the workflow before paying anything.