Claude 4 Explained: Models, Features & Uses
Claude 4 is here — and it’s no longer a future announcement. The Claude 4 model family includes Opus, Sonnet, and Haiku variants, all available now through claude.ai and the Anthropic API. This guide explains what Claude 4 is, how the models compare, and when to use each one.
ClaudeAIHub. For the latest model information, visit Anthropic’s model documentation.
What Is Claude 4?
Claude 4 is the current generation of Claude AI models developed by Anthropic. Where earlier Claude generations (Claude 2, Claude 3, Claude 3.5) were focused on building general AI capabilities, Claude 4 represents Anthropic’s most capable models to date, with particular advances in agentic coding, long-context reasoning, and extended thinking workflows.
The Claude 4 family uses the same naming structure as previous generations: Opus (most capable), Sonnet (balanced speed and intelligence), and Haiku (fastest). The current Claude 4 models are versioned with point releases — for example, Claude Sonnet 4.6 is a more recent Sonnet model than the earlier 4.5 or 4.0 releases.
Current Claude 4 Models
As of mid-2026, the three current Claude 4 tier models are:
| Model | Description | Context window | API pricing (per MTok) | Knowledge cutoff |
| Claude Opus 4.8 | Most capable — complex reasoning, agentic coding | 1M tokens | $5 input / $25 output | January 2026 |
| Claude Sonnet 4.6 | Best speed + intelligence balance | 1M tokens | $3 input / $15 output | August 2025 |
| Claude Haiku 4.5 | Fastest, near-frontier intelligence | 200k tokens | $1 input / $5 output | February 2025 |
Source: Anthropic model documentation (verified June 2026). Pricing is per million tokens and applies to the Anthropic API. Users of claude.ai pay monthly subscription fees, not per-token rates.
Above the Claude 4 family: on June 9, 2026, Anthropic launched Claude Fable 5 — its most capable widely released model ($10/$50 per MTok, 1M token context). The Claude 4 models above remain the core tiers for most users.
Claude Opus 4.8
Claude Opus 4.8 is Anthropic’s most capable Opus-tier model. It is designed for tasks that require the deepest reasoning, most complex analysis, and the most sophisticated multi-step workflows. Anthropic specifically described it as having a “step-change improvement in agentic coding” over the previous Opus 4.6.
For complete specs, API ID, and a comparison with Opus 4.7, see the Claude Opus 4.8 guide.
Opus 4.8 is best used for:
- Complex reasoning and analysis tasks
- Agentic coding workflows with Claude Code
- Long document analysis (up to 1M tokens)
- Tasks where quality matters more than speed
Opus 4.8 supports Adaptive Thinking, which lets the model dynamically adjust its reasoning depth based on task complexity.
Claude Sonnet 4.6
Claude Sonnet 4.6 is Anthropic’s recommended model for most everyday tasks. Anthropic describes it as “the best combination of speed and intelligence” — it runs faster than Opus while still handling complex writing, coding, and research tasks well.
Sonnet 4.6 is best for:
- Everyday writing, editing, and research
- Coding assistance and debugging
- Document summarization and analysis
- Conversational use where speed matters
Sonnet 4.6 supports both Extended Thinking and Adaptive Thinking, giving it flexible reasoning modes for tasks that benefit from deeper analysis.
Claude Haiku 4.5
Claude Haiku 4.5 is the fastest model in the Claude 4 family. Anthropic describes it as having “near-frontier intelligence” at a fraction of the compute cost. It has a smaller context window (200k tokens) but is ideal for high-volume, speed-sensitive applications.
Haiku 4.5 is best for:
- High-volume API applications where cost and latency matter
- Quick question-answering and lightweight tasks
- Summaries of shorter documents
- Real-time or interactive applications
Is Claude 4 Better Than Claude 3.5?
Yes — Claude 4 models are the current generation and more capable than Claude 3.5 models across the board. Claude 3.5 Sonnet and Claude 3.5 Haiku were the previous generation. They have been superseded by the Claude 4 family (Opus 4.x, Sonnet 4.x, Haiku 4.x). Anthropic’s model documentation notes that migrating from previous models to Claude 4 typically yields larger performance improvements than moving between sub-versions within the same generation.
Claude 3.5 models are still available via the API for users who haven’t yet migrated, but Anthropic recommends moving to Claude 4 equivalents. Two older Claude 4 models — Claude Sonnet 4 and Claude Opus 4 (the initial 4.0 releases) — have been deprecated and will be retired June 15, 2026.
Claude 4 for Claude.ai App Users
If you use Claude at claude.ai rather than the API, you don’t choose a specific model version — Claude automatically uses a current model appropriate to your plan. Free plan users get access to current Claude models with usage limits. Pro and Max plan users get higher usage limits and access to the most capable models.
See our Claude pricing guide for a full comparison of what each plan includes, or our Claude models guide for a deeper dive on model differences and how to choose.
Frequently Asked Questions
Is Claude 4 available now?
Yes. Claude 4 models are available now through claude.ai (the consumer app) and the Anthropic API. The current Claude 4 models are Claude Opus 4.8, Claude Sonnet 4.6, and Claude Haiku 4.5.
What are the Claude 4 models?
The current Claude 4 models are Claude Opus 4.8 (most capable, best for complex tasks), Claude Sonnet 4.6 (balanced speed and intelligence, best for everyday use), and Claude Haiku 4.5 (fastest, best for high-volume or speed-sensitive tasks).
Is Claude 4 better than Claude 3.5?
Yes. Claude 4 models are the current generation and supersede Claude 3.5 models. Anthropic notes that upgrading from previous Claude generations to Claude 4 typically produces larger performance improvements than moving between sub-versions. The Claude 3.5 models are still accessible via API but are no longer Anthropic’s recommended versions.
Which Claude 4 model should I use?
For complex tasks requiring deep reasoning or agentic coding, use Claude Opus 4.8. For everyday writing, coding, and research, Claude Sonnet 4.6 is usually the best balance. For fast, high-volume, or lightweight tasks, Claude Haiku 4.5 is the most efficient. Claude.ai app users don’t choose manually — the platform selects an appropriate model.
Is Claude 4 free?
You can access Claude 4 models for free at claude.ai with usage limits. Claude Pro ($20/month) and Claude Max ($100+/month) plans give significantly more usage. The Anthropic API charges per-token rates depending on the model chosen.