Claude Opus 4.5

Available · Language, Multimodal, Reasoning

Claude Opus 4.5 is a language model in Anthropic's Opus line that accepts text and images, with a 200K-token context window, extended thinking and an effort parameter for trading thoroughness against token use. It is offered in the Claude apps, on the Anthropic API, Amazon Bedrock, Google Cloud Vertex AI and Microsoft Foundry, at a lower price than earlier Opus models. [1]Capabilities [2] [3]Claude Opus 4.5 Summary Table, Access Surfaces [4]November 24, 2025 Primary source

Timeline of Claude Opus 4.5 →

Claims and evidence

Released 24 November 2025 Primary source[2] [4]November 24, 2025 [1]Availability

Status AvailableListed by Anthropic as a legacy model that is still available; retirement not sooner than 2026-11-24. Primary source[1]Availability [5]Model status

Successor of Claude Opus 4.1 EditorialEditorial link along the Opus tier: the announcement compares the model with earlier Opus models without naming a predecessor, and Claude Opus 4.1 was the most recent Opus release before it. Primary source[2]

Change · Other Priced at $5 and $25 per million input and output tokens, against $15 and $75 for Claude Opus 4.1, which kept the Opus 4 price.Compared with Claude Opus 4.1 Primary source[2] [4]November 24, 2025 [6] [7]
Change · Reasoning Supports the effort parameter, in public beta at launch, which trades response thoroughness against token use.Compared with Claude Opus 4.1 Primary source[4]November 24, 2025 [8]section 1.1.2

Input text, image Primary source[1]Capabilities [3]Claude Opus 4.5 Summary Table, Modalities
Output text Primary source[1]Capabilities
Feature Reasoning mode Primary source[1]Capabilities [8]section 1.1.2
Context window 200K tokens Primary source[1]Capabilities
Parameters Not disclosedNot disclosed by Anthropic. No claim madeNo source
Access consumer app, API, cloud partner Primary source[2] [3]Claude Opus 4.5 Summary Table, Access Surfaces

Lineage

Predecessors

Claude Opus 4.1 · 5 August 2025

Successors

Claude Opus 4.6 · 5 February 2026

Based on

Not derived from another model.

Variants and derived

None recorded.

Siblings

None recorded.

All ancestors

Claude · 14 March 2023
Claude 2 · 11 July 2023
Claude 2.1 · 21 November 2023
Claude 3 Opus · 4 March 2024
Claude Opus 4 · 22 May 2025
Claude Opus 4.1 · 5 August 2025

All descendants

Claude Opus 4.6 · 5 February 2026
Claude Opus 4.7 · 16 April 2026
Claude Opus 4.8 · 28 May 2026
Claude Opus 5 · 24 July 2026
Claude Opus 5.5 · 22 September 2026

Related AI Radar coverage

AI Radar coverage starts in June 2026; no coverage linked yet.

All model releases from Anthropic on AI Radar →

Organisation: Anthropic
Family: Claude Opus
Generation: 4.5
Timeline date: 24 November 2025
Released
Prominence: Standard release Editorial
Also known as: claude-opus-4-5-20251101, claude-opus-4-5, Opus 4.5
Record: Full record
Last reviewed: 1 October 2026

Sources

[1] Claude Opus 4.5

Documentation · Anthropic

Provenance
Primary

Availability
Active

Last checked
8 October 2026

Original ↗ https://platform.claude.com/docs/en/models/opus-4-5/overview Model page in the Claude Platform docs; living page, content as seen on 2026-10-01.
[2] Introducing Claude Opus 4.5

Announcement · Anthropic · published 24 November 2025

Provenance
Primary

Availability
Active

Last checked
8 October 2026

Original ↗ https://www.anthropic.com/news/claude-opus-4-5
[3] Anthropic’s Transparency Hub

Model card · Anthropic

Provenance
Primary

Availability
Active

Last checked
8 October 2026

Original ↗ https://www.anthropic.com/transparency/model-report Model Report section with one summary table per model (description, release month, access surfaces, modalities, knowledge cutoff). Living page; content as seen on 2026-10-01. https://www.anthropic.com/transparency shows the same content.
[4] Claude Platform release notes

Release notes · Anthropic

Provenance
Primary

Availability
Active

Last checked
8 October 2026

Original ↗ https://platform.claude.com/docs/en/release-notes/overview Living page; content as seen on 2026-10-01; earliest entry May 2024. The old address https://docs.anthropic.com/en/release-notes/api redirects here (301 to platform.claude.com/docs/en/release-notes/api, then 307).
[5] Model deprecations

Deprecation notice · Anthropic

Provenance
Primary

Availability
Active

Last checked
8 October 2026

Original ↗ https://platform.claude.com/docs/en/about-claude/model-deprecations Living page; content as seen on 2026-10-01. The old address https://docs.anthropic.com/en/docs/about-claude/model-deprecations redirects here (301, then 307 via platform.claude.com/docs/en/docs/about-claude/model-deprecations). The page says its dates apply to the Claude API, Claude Platform on AWS and Microsoft Foundry; Amazon Bedrock and Google Cloud set their own schedules.
[6] Claude Opus 4.1

Announcement · Anthropic · published 5 August 2025

Provenance
Primary

Availability
Active

Last checked
8 October 2026

Original ↗ https://www.anthropic.com/news/claude-opus-4-1
[7] Introducing Claude 4

Announcement · Anthropic · published 22 May 2025

Provenance
Primary

Availability
Active

Last checked
8 October 2026

Original ↗ https://www.anthropic.com/news/claude-4 Announces Claude Opus 4 and Claude Sonnet 4 together.
[8] System Card: Claude Opus 4.5

System card · Anthropic · published November 2025

Provenance
Primary

Availability
Active

Last checked
8 October 2026

Original ↗ https://www.anthropic.com/claude-opus-4-5-system-card Published link to a PDF. It redirects (307, temporary) via https://www.anthropic.com/document/claude-opus-4-5-system-card to a content-hashed file that changes with each revision; on 2026-10-01 that was https://www-cdn.anthropic.com/bf10f64990cfda0ba858290be7b8cc6317685f47/Claude%20Opus%204.5%20System%20Card.pdf. The cover gives November 2025; the changelog inside lists revisions dated 2025-11-24, 2025-11-25 and 2025-12-05.