Welcome to Claude AI, Anthropic’s safety-first family of large-language models — now entering the Claude 4 era. Harness frontier performance, transparent reasoning and enterprise-grade trust in one powerful platform. Prefer native apps? Grab our desktop and mobile apps here to chat without juggling browser tabs.
Claude AI blends cutting-edge intelligence with Anthropic’s uncompromising commitment to Helpful, Honest & Harmless behavior. Use it to digest hundred-page contracts, refactor legacy code, draft investor memos or orchestrate fully autonomous AI agents — all while knowing that rigorous AI Safety Level 3 safeguards are active by default.
Why Choose Claude AI? Five Reasons Users Switch
- Built-in Constitutional AI: A clear rule-set inspired by human-rights principles trains Claude to refuse unsafe requests and reduce bias without endless human red-teaming.
- Mammoth Context Window: Up to 200K tokens lets Claude 4 models reason over entire codebases, quarterly filings or book manuscripts in one pass.
- Hybrid Reasoning Architecture: Claude 4 can blast back an instant reply or engage extended thinking for multi-hour tasks — you control the “thinking budget.” Need live data mid-chat? Web Search streams fresh sources straight into the answer.
- Benchmark-Leading Coding & Logic: Claude 4 Sonnet scores a record 72.7 % on SWE-bench while flagship Opus nails multi-step agentic challenges.
- No-Train-On-Your-Data Policy: Anthropic contractually guarantees that customer API data stays private, a critical edge for regulated industries.
What’s New in Claude 4?
1. Dual-Model Line-Up
Claude 4 Sonnet delivers enterprise-grade performance at an affordable price, while Claude 4 Opus tackles the toughest R&D problems with frontier-level reasoning. Each shares the same 200K token window and transparent safety protections.
2. Autonomous Coding Sessions
In benchmark demos, Opus coded unsupervised for seven straight hours, landing bug-fixes and refactors across a live repo. Sonnet matches that power on many day-to-day tasks and now ships inside GitHub Copilot’s next-gen agent.
3. Visible Thought with Safety Filters
Turn on Extended Thinking to watch Claude lay out its chain-of-thought in plain English summaries — ideal for auditing reasoning or teaching junior teammates.
4. Persistent Memory Files
Grant file access and Claude writes its own “sticky notes,” remembering project decisions and key facts across sessions so you never have to repeat context.
5. Instant Tool Invocation
The new API integrates a sandboxed Python runner, Model Context Protocol connector and 1-hour prompt caching — slashing latency and cost for long-running agent workflows.
Core Capabilities at a Glance
1. Deep Text Analytics
- Summarize class-action lawsuits or 10-K filings in minutes.
- Extract structured data from unstructured PDFs or emails.
- Generate policy drafts, marketing copy and technical documentation with consistent voice.
2. Best-in-Class Coding Assistant
- Auto-generate tests, convert legacy frameworks and explain diff outputs.
- Use Claude Code inside VS Code or JetBrains IDEs for inline suggestions.
- Stream large code patches up to 32K tokens in one response.
3. Vision & Data Understanding
- Interpret charts, engineering diagrams and product photos.
- Answer data-driven questions by combining text and image context.
- Pair with the Files API to store and query visual assets at scale.
4. Agentic Workflow Automation
- Connect Claude to CRMs, BI tools or ticketing systems via the MCP connector.
- Let it schedule campaigns, draft follow-ups and update dashboards autonomously.
- Monitor every step through concise reasoning summaries for auditability.
Claude AI vs. GPT-4o & Gemini 2.5: The 2025 Scorecard
Against OpenAI GPT-4o
- Safety Transparency: Constitutional AI rules are public; GPT’s policy weights are opaque.
- Cheaper Long Context: 200K tokens standard versus GPT’s paid “Long Context” add-on.
- Higher SWE-bench: 72.7% vs 69% for GPT-4o (May 2025 snapshot).
Against Google Gemini 2.5
- Enterprise Privacy: No-train-on-data by default; Gemini requires opt-outs.
- Visible Reasoning: Extended Thinking exposes chain-of-thought; Gemini keeps it hidden.
- Dedicated Focus: Anthropic invests 100% in safe AI — not split across ads, search and hardware.
Bottom line: Choose Claude when you need provable safety, vast context handling and best-in-class coding — without surrendering data control. See how Claude stacks up against ChatGPT.
Getting Started
- Web, Mobile & Voice Mode: Chat or speak with Claude for free, upgrade to Pro or Max for higher limits and Claude 4 models.
- API & SDKs: Plug Claude into Python or TypeScript back-ends with pay-as-you-go pricing.
- Download Claude App: Install the desktop or mobile launcher from Windows, macOS, Linux or Play Store.
- Real-time Status: Check uptime and incident reports before you start critical work.
- AWS Bedrock & Google Vertex AI: Deploy within your existing cloud, inherit IAM and audit trails.
- Enterprise Plans: Unlock 500K context windows, dedicated capacity and SOC 2 reports.
Claude AI FAQ
A: Claude critiques its own draft answers against an explicit charter of human-centric principles, producing consistent refusals of harmful content without ad-hoc human judgment.
A: Use Sonnet for day-to-day knowledge work and coding at $3 / M input tokens. Choose Opus for frontier research, multi-hour agents or projects demanding the absolute highest reasoning scores.
A: Yes. Enable the Browse tool on claude.ai or call the Web Search tool via the API to augment the model’s late-2024 knowledge cutoff with fresh data.
A: No. API and Enterprise traffic is excluded from training by default, and chat data is retained solely for abuse monitoring unless you opt-in to share.
A: In chat, toggle “Show reasoning.” In the API, set extended_thinking=true and configure a token or time budget.
Ready to Build with Responsible AI?
Claude AI delivers the intelligence of a frontier model and the peace of mind of rigorous guardrails. Join the thousands of teams already shipping faster, writing clearer and solving bigger problems with Claude.