# Claude Opus 4.8

Claude Opus 4.8 is an Anthropic language model released May 28, 2026; Anthropic's newest language model in our dataset is Claude Haiku 5.5. Proprietary, API access only. Anthropic's Claude Opus 4.8, launched May 28, 2026 with a 1M-token context by default and 128k max output. Verified against vendor sources on Oct 26, 2026.

Last verified: 2026-10-26 · Evidence: Reported · Canonical: https://theagenticweekly.com/models/claude-opus-4-8 · JSON: https://theagenticweekly.com/api/models/claude-opus-4-8

## Key facts

| Fact | Value | Source |
|---|---|---|
| Vendor | Anthropic |  |
| Released | May 28, 2026 | https://platform.claude.com/docs/en/release-notes/overview |
| API id | `claude-opus-4-8` | https://platform.claude.com/docs/en/release-notes/overview |
| Context window | 1,000,000 tokens (1M) | https://platform.claude.com/docs/en/release-notes/overview |
| Max output | 128,000 tokens | https://platform.claude.com/docs/en/release-notes/overview |
| Licence | Proprietary (API) | https://platform.claude.com/docs/en/about-claude/models/overview |
| Pricing | $5 in / $25 out per 1M tokens | https://platform.claude.com/docs/en/release-notes/overview |

## What we tested

Nothing yet. We have not run Claude Opus 4.8 ourselves, so every fact here is Reported from the sources below.

## Not verified, left out

- Price is stated in the Claude Opus 5 release note ("the same pricing as Claude Opus 4.8").

## Sources

- [Claude Platform release notes](https://platform.claude.com/docs/en/release-notes/overview)
- [Anthropic models overview](https://platform.claude.com/docs/en/about-claude/models/overview)

Data licence: CC BY 4.0. Data: Agentic Weekly (https://theagenticweekly.com), CC BY 4.0.