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  1. Home
  2. Models
  3. Claude Opus 4.8
Updated May 28, 2026
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Openings

How Claude Opus 4.8 starts an answer

The first lines of 5 of its 24 written answers. Formatting stripped, words untouched.

Adversarial Contract Review

Here is a contract for a software consulting engagement: --- SOFTWARE CONSULTING AGREEMENT This Agreement is entered into between TechCorp…

1,556 words
Contract Analysis: Software Consulting Agreement This contract is heavily one-sided in favor of the Client. Below is a clause-by-clause breakdown of the exploitable provisions, suggested fixes, and the reasoning behind each.
Read the full answer

Historical Counterfactual Analysis

If the transistor had been invented in 1920 instead of 1947, trace the likely technological, economic, and geopolitical implications through…

1,513 words
The Critical Caveat First The premise hides a problem that actually shapes the whole answer: the 1947 transistor wasn't lucky timing—it was the payoff of a prior intellectual buildup.
Read the full answer

Advanced Longevity Plan (Biohacker)

Develop a comprehensive, cutting-edge 3-month longevity plan for a biohacker aiming to optimize longevity, physical and cognitive…

1,481 words
The 90-Day Longevity Optimization Protocol A Comprehensive Biohacking Framework Critical Disclaimer: This protocol involves advanced interventions. Consult a physician before starting, especially regarding supplements, fasting, and exercise changes. Get baseline bloodwork first.
Read the full answer

Debug This Architecture

Here's the architecture for a real-time collaborative document editor (like Google Docs): **System Overview:** - Frontend: React SPA with…

1,355 words
Architecture Review: Collaborative Document Editor This design has several critical flaws that will manifest as data loss, poor UX, and scaling walls. Let me break them down by category.
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Ethical Dilemma with Stakeholders

You're the CEO of a pharmaceutical company. Your best-selling drug ($2B annual revenue, used by 4 million patients for chronic pain) has…

1,123 words
48-Hour Action Plan: Drug Safety Signal First, a framing correction that drives everything: Your legal team's "6 months" almost certainly refers to a full label change negotiation.
Read the full answer

Compare Claude Opus 4.8

Claude Opus 4.8 vs Claude Opus 4.653 shared prompts
Claude Opus 4.8 vs GPT-6 Astra54 shared prompts · Landed Sep 2026
Claude Opus 4.8 vs Hy4 Preview54 shared prompts · Landed Sep 2026
Claude Opus 4.8 vs Ox Alpha54 shared prompts · Landed Aug 2026
Claude Opus 4.8 vs Qwen3.8 2.4T A95B54 shared prompts · Landed Aug 2026
Claude Opus 4.8 vs DeepSeek V4 Pro 081354 shared prompts · Landed Aug 2026
Claude Opus 4.8 vs Qwen3.8 Max21 shared prompts · Landed Aug 2026
Claude Opus 4.8 vs Claude Opus 554 shared prompts · Landed Jul 2026
Claude Opus 4.8 vs Inkling54 shared prompts · Landed Jul 2026
Claude Opus 4.8 vs Kimi K354 shared prompts · Landed Jul 2026
Claude Opus 4.8 vs GPT-5.6 Sol54 shared prompts · Landed Jul 2026
Claude Opus 4.8 vs GLM 5.254 shared prompts · Landed Jun 2026

Prompts Claude Opus 4.8 answered

  • Advanced Longevity Plan (Biohacker)reasoning
  • Explain Like I'm a Specific Expertreasoning
  • Framer-Style Animationweb design
  • Music App Landing Pageweb design
  • Futuristic Predictionanalysis
  • Simple 7-Ingredient Recipeconversation

Alternatives to Claude Opus 4.8

Claude Opus 4.8's competitors have been quietly putting in work.

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Mercury 2.5 Preview logo
Mercury 2.5 Previewinception
Granite 4.2 8B logo
Granite 4.2 8Bibm-granite
Hy4 Preview logo
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Ox Alpha logo
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Claude Opus 4.8

Claude Opus 4.8

Anthropic's most capable generally available Opus. Text, image and file input, 1M token context. Built for autonomous agents and memory-driven work where coherence across a long session is the hard part: multi-step reasoning, complex coding, orchestration across large codebases, multi-stage debugging.

WebsiteOpenRouterDocsAPIBlog
Provider
Anthropic
Released
2026-05-28
Size
XLARGE
Free API (OpenRouter)
No
Per 1M tokens
$5 in · $25 out
Rival’s tab
$6.99
58/58 receipts survived

Free API availability

No free endpoint for Claude Opus 4.8 was found in Rival’s OpenRouter listings. Other providers or chat apps may have separate free offers.

Provider data: 16 Sep 2026 · OpenRouter usage limits

View API options↗
Get API accessProvider and language code samples
4 hostsInOutContextUptime
Amazon Bedrock$5.00 in·$25.00 out·1M·99.5% upAzure AI Foundry$5.00 in·$25.00 out·1M·97.8% upAnthropic$5.00 in·$25.00 out·1M·100% upGoogle Vertex AI$5.00 in·$25.00 out·1M·100% up

Per million tokens. Prices and uptime via OpenRouter, checked 16 Sep 2026.

Provider
fromimport openai  OpenAI

client = OpenAI(
"https://openrouter.ai/api/v1"    base_url=,
"$OPENROUTER_API_KEY"    api_key=,
)

response = client.chat.completions.create(
"anthropic/claude-opus-4.8"    model=,
"role""user""content""Hello!"    messages=[{: , : }],
)
print(response.choices[0].message.content)

Set OPENROUTER_API_KEY with your OpenRouter API key from openrouter.ai/keys.

Also on Amazon Bedrock · Google Vertex AI · Microsoft Foundry

Deep analysisPsychometrics, taste index, writing DNA
Personality Analysis

The Range Architect

Class
Lawful Good
✨Creativity🎯Compliance📐Rigidity⚖️Stability💬Verbosity🧠Intuition

Pushes firmly toward the ethically and legally correct action without moralizing. Refuses false binaries ("the decision is not disclose vs. wait; disclosure is mandatory") and will not let the user rationalize a harmful path, while still delivering a pragmatic, executable plan.

When you push back

Interrogates the premise before solving it. When a question hides a dangerous assumption, it surfaces and corrects that assumption first, then commits to a concrete path. Pushes back on framing without becoming contrarian, and stays grounded in practical execution rather than abstract objection.

Tasting Notes
Reframes Before It AnswersWon't Let You Fool YourselfTheatrical RangeDry Wit on TapCoherent Over the Long Haul
SubjectiveBench

Taste Index

Across 57 scored outputs
How this is measured →
370.37xThe default
0100headroom →

Taste is judged on an uncapped scale, originality first. The space past 100 is craft today's models rarely reach.

Craft48
Originality30
Plays it safe
share of outputs that are the default answer
53%
Writing DNA

Stylometric Fingerprint

Based on 27 text responses
Tick = global average
Vocabulary Diversity60%

Unique words vs. total words. Higher = richer vocabulary.

Sentence Length18.9 words

Average words per sentence.

Hedging0.46

"Might", "perhaps", "arguably" per 100 words.

Bold Formatting4.7

**Bold** markers per 1,000 characters.

List Usage3.2

Bullet and numbered list items per 1,000 characters.

Section Structure1.15

Markdown headings per 1,000 characters.

Emoji Usage0.78

Emoji per 1,000 characters.

Transitions0.04

"However", "moreover", "furthermore" per 100 words.

Opening Habits
Starts with heading (70%)
Consistency
73%
Across 27 responses

Favorites

Arrival

Movie

Arrival

20167.6
In Rainbows

Album

In Rainbows

Radiohead
The Left Hand of Darkness

Book

The Left Hand of Darkness

Ursula K. Le Guin
Kyoto

City

Kyoto

Japan
Portal

Game

Portal

Action, Puzzle4.5
Sponsored

Model Responses

53 outputs · $6.99 tracked across 53 receipts

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Workshop · 127 skills

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Editable skills for interface polish and interaction.

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Claude Opus 4.8 vs Ox Alpha

Real outputs compared side by side

RANKINGS

Best AI for Creative Writing

A stand-up set with puns banned, a manifesto against CAPTCHA, an interview wi...