# Claude Opus 4.8

> Anthropic's May 2026 Opus-tier release: complex reasoning and long-horizon agentic coding at $5/$25 per million tokens.

- Maker: Anthropic
- Line: Claude Opus
- Canonical page: https://ai-tldr.dev/models/claude-opus-4-8/
- Updated: 2026-07-25

## In short

Claude Opus 4.8 is Anthropic's Opus-tier model released on May 28, 2026, positioned for complex reasoning, long-horizon agentic coding, and high-autonomy work. It became generally available via the Claude API, Amazon Bedrock, Google Cloud Vertex AI, and Microsoft Foundry, and was succeeded in the Opus line by Claude Opus 5 on July 24, 2026.

## Facts

| Fact | Value | Source |
| --- | --- | --- |
| Context window | 1M (max output 128K) | [1] |
| Input price | $5.00 / 1M tokens (cached $0.50) | [2] |
| Output price | $25.00 / 1M tokens | [2] |
| Licence | Proprietary · API only | [1] |
| Released | 28 May 2026 | [3] |
| Parameters | Undisclosed | [1] |
| Knowledge cutoff | Jan 2026 | [1] |

## Sources

1. [Models overview (specs)](https://platform.claude.com/docs/en/about-claude/models/overview)
2. [Anthropic pricing](https://platform.claude.com/docs/en/about-claude/pricing)
3. [Introducing Claude Opus 4.8](https://www.anthropic.com/news/claude-opus-4-8)

## Overview

Claude Opus 4.8 is Anthropic's Opus-tier model released on May 28, 2026, positioned for complex reasoning, long-horizon agentic coding, and high-autonomy work. It became generally available via the Claude API, Amazon Bedrock, Google Cloud Vertex AI, and Microsoft Foundry, and was succeeded in the Opus line by Claude Opus 5 on July 24, 2026.

It ships with a 1M-token context window at standard pricing and supports up to 128K output tokens. The model accepts text and image input and uses adaptive thinking (always on); on Opus 4.8 the effort parameter defaults to high across the API and Claude Code.

Pricing is $5 per million input tokens and $25 per million output tokens, with cache reads at $0.50 per million. An optional research-preview Fast mode trades higher per-token cost ($10 input / $50 output) for significantly faster output. Anthropic deprecated Fast mode on Opus 4.8 on October 30, 2026 and scheduled its removal for November 30, 2026; after that date, requests to claude-opus-4-8 with speed set to fast return an error, and Anthropic points users who need the speedup to Claude Opus 5.5.

## Benchmarks

- Online-Mind2Web: 84% ([source](https://www.anthropic.com/news/claude-opus-4-8))

## Pricing

- Input: $5.00 / 1M tokens
- Cached input: $0.50 / 1M tokens
- Output: $25.00 / 1M tokens

Source: https://platform.claude.com/docs/en/about-claude/pricing

## Strengths

- Frontier reasoning and long-horizon agentic coding
- 1M-token context window billed at standard per-token rates
- Adaptive thinking with a high default effort level for deep reasoning
- Strong agentic web/computer-use performance (84% on Online-Mind2Web)
- Direct reasoning over PDFs, diagrams, and other unstructured visual content

## Best for

- Reach for it when you need the most capable model for multi-step agentic coding across a large codebase.
- Reach for it when a task needs deep reasoning over very long documents within a 1M-token context.
- Reach for it for high-autonomy agent workflows where reliability matters more than per-token cost.

## How to access

- [Anthropic API](https://platform.claude.com/docs/en/about-claude/models/overview) — model id `claude-opus-4-8`

## Claude Opus versions

- [Claude Opus 5](https://ai-tldr.dev/models/claude-opus-5/) (24 July 2026)
- Claude Opus 4.8 (28 May 2026) — this page
- [Claude Opus 4.7](https://ai-tldr.dev/models/claude-opus-4-7/) (16 April 2026)
- [Claude Opus 4.6](https://ai-tldr.dev/models/claude-opus-4-6/) (5 February 2026)
- [Claude Opus 4.5](https://ai-tldr.dev/models/claude-opus-4-5/) (24 November 2025)
- [Claude Opus 4.1](https://ai-tldr.dev/models/claude-opus-4-1/) (5 August 2025)
- [Claude Opus 4](https://ai-tldr.dev/models/claude-opus-4/) (22 May 2025)
- [Claude 3 Opus](https://ai-tldr.dev/models/claude-3-opus/) (4 March 2024)

## FAQ

### How much does Claude Opus 4.8 cost?

Claude Opus 4.8 costs $5 per million input tokens and $25 per million output tokens on the Anthropic API. Prompt-cache reads are $0.50 per million tokens. An optional research-preview Fast mode raises this to $10 input and $50 output per million tokens for faster output; Anthropic deprecated Fast mode on Opus 4.8 and removes it on November 30, 2026.

### What is the context window of Claude Opus 4.8?

Claude Opus 4.8 has a 1M-token context window, available at standard per-token pricing, and can generate up to 128K output tokens in a single synchronous response. On Microsoft Foundry the context window is 200K tokens.

### When was Claude Opus 4.8 released?

Anthropic made Claude Opus 4.8 generally available on May 28, 2026, across the Claude API, Amazon Bedrock, Google Cloud Vertex AI, and Microsoft Foundry. Its reliable knowledge cutoff is January 2026.

## Links

- [Introducing Claude Opus 4.8](https://www.anthropic.com/news/claude-opus-4-8)
- [Claude Opus product page](https://www.anthropic.com/claude/opus)
- [Models overview (specs)](https://platform.claude.com/docs/en/about-claude/models/overview)
- [Anthropic pricing](https://platform.claude.com/docs/en/about-claude/pricing)
- [Fast mode (Claude API docs)](https://platform.claude.com/docs/en/build-with-claude/fast-mode)
- [Claude Code v2.1.316 release notes (Fast mode deprecation for Opus 4.8)](https://github.com/anthropics/claude-code/releases/tag/v2.1.316)

Source: AI/TLDR LLM registry, https://ai-tldr.dev/models/claude-opus-4-8/