Claude AI Chat: An Independent Guide to Anthropic’s Claude

What is Claude AI Chat?

Claude is a family of AI models made by Anthropic, an AI safety company founded in 2021 by Dario and Daniela Amodei and other former OpenAI researchers. “Claude AI Chat” is the everyday act of chatting with Claude — asking questions, writing and editing, analysing documents, and getting coding help — through Anthropic’s official app at claude.ai.

To keep the names straight: the company is Anthropic; the product is Claude; the place you chat is claude.ai; the developer platform is platform.claude.com; and c-ai.chat (this website) is an independent guide that is not affiliated with Anthropic. For the full background, read our What is Claude AI primer.

Where to use the official Claude chat

There is one official place to chat with Claude — claude.ai — available across every surface. Sign-in is required (Google, Apple, email, or work SSO); creating an account is free. New Claude accounts require one-time phone verification using a supported phone number, and Anthropic says this step cannot be skipped.

• Web: claude.ai in any modern browser — the most complete surface.
• Mobile: official iOS and Android apps.
• Desktop: native macOS and Windows apps, plus an official Linux desktop app in beta (Ubuntu and Debian, x64/arm64).
• Developers: the Claude API and Claude Code for building with Claude directly.

Download links for every platform are on Anthropic’s official download page — see our step-by-step Claude download guide and login & access help.

Claude plans: Free, Pro, Max, Team, Enterprise & API

The Claude app is billed by plan; the API is billed by token. Plan usage is governed by session-based limits (roughly five-hour reset windows) plus weekly limits — not a fixed daily message count.

• Free — $0. Claude Sonnet 5 and Haiku 4.5 with session-based usage limits.
• Pro — $20/month (or $17/month billed annually). Adds Opus 4.8, Claude Code, Cowork, Projects and higher limits. Fable 5 is API-first — subscription access can require usage credits.
• Max — from $100/month. 5× or 20× Pro usage, higher output limits and priority.
• Team — $25/seat/month ($20 annual) with SSO and admin controls; Team Premium $125/seat ($100 annual).
• Enterprise — self-serve & sales-assisted. $20/seat base plus usage at API rates; SCIM, audit logs, role-based access and data-residency options.
• Claude API — pay-as-you-go per-token billing (see the model table above).

Full plan-by-plan detail is in our Claude pricing guide and the Claude API reference. Official prices: claude.com/pricing.

Key Claude features & product surfaces

Claude is more than a chat box. The app and platform add a set of working tools around the models:

• Projects, Artifacts & Research — organise context, generate editable outputs, and run deeper multi-step research.
• Connectors, Skills, Sub-agents & Hooks — an official plugin ecosystem with built-in marketplaces; connectors can read and take actions in tools like Google Drive, Gmail and Slack.
• Claude Cowork — agentic execution for knowledge work (explained below).
• Claude Code — Anthropic’s coding agent in the terminal, IDEs, desktop and on the web.
• Microsoft 365 — Claude for Excel, PowerPoint and Word are generally available on paid plans; Outlook is in beta.
• Vision, voice, extended thinking & file upload — analyse images and PDFs (chat uploads up to 500 MB per file and 20 files per chat; Project files up to 30 MB per file), talk to Claude, and switch on longer reasoning.

Browse everything in the Claude features guide.

Claude Code & the Claude API

Claude Code is Anthropic’s agentic coding tool. It runs in your terminal and IDE, in the desktop app, and on the web at claude.ai/code, where it works on connected GitHub repositories in managed cloud environments and can edit code and run tests. It uses a CLAUDE.md file for persistent project instructions, and includes a plugin system, Remote Control, and an experimental Agent Teams mode. Claude Code is available on Pro, Max, Team and Enterprise (not the Free plan).

The Claude API gives you the same models pay-as-you-go, with prompt caching (up to 90% off cached input) and a Batch API (50% off). Estimate a workload with our Claude API cost calculator, then start with the Claude API guide and Claude Code hub. Official docs: platform.claude.com.

What is Claude Cowork?

Claude Cowork brings Claude Code-style agentic execution to knowledge work — no terminal required. You describe a multi-step task and Claude carries it out, producing real files such as decks, spreadsheets, documents and research write-ups. The agent loop and code execution run on Anthropic-managed servers in an isolated environment, and your sessions and files are saved to your Claude account, so a running remote task keeps going after you close your laptop, as long as the task doesn’t need local files, your browser, or your computer (those keep the desktop app and device in the loop) (Anthropic: “Close your laptop, Claude keeps going”).

Cowork is a paid feature (Pro, Max, Team and Enterprise) available on web and desktop, with mobile in beta. It is not a shared team chat room, and “Projects inside Cowork” are not the same thing as Cowork itself. Full explanation in our Claude Cowork guide.

Claude compared with ChatGPT, Gemini and others

Claude, ChatGPT and Gemini are separate products from Anthropic, OpenAI and Google. We compare them on specific tasks — coding, long-document work, writing, vision, team controls and price — and we date each comparison and name the models tested, rather than declaring a single “winner”. Where we test, we describe the method and show limitations.

Start with Claude vs ChatGPT, Claude vs Gemini, or the full comparisons hub.

Safety, privacy & data use

Data retention and model training are separate questions, and the rules differ by plan (Consumer, Team, Enterprise and API). A few essentials, verified against Anthropic’s own documentation:

• Zero Data Retention is not universal — it applies only under a specific covered agreement.
• Claude is not generally self-hosted or on-prem; managed deployments run via Amazon Bedrock, Google Cloud and Microsoft Foundry.
• Incognito/temporary chats aren’t used for training and don’t appear in history, but “not in history” is not the same as immediate server deletion (default retention around 30 days).
• You must be at least 18 years old, or the minimum age required to consent to use the services in your location, whichever is higher.

Details in our Claude privacy guide and is Claude AI safe? Official policies: privacy.claude.com and Anthropic Trust Center.