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Claude Opus 4 vs Claude Opus 4.5

Claude Opus 4.5 significantly outperforms across most benchmarks. Claude Opus 4.5 is 3.0x cheaper per token.

Anthropic · Anthropic · Updated for 2026

Which is better?

Claude Opus 4 outperforms in 0 benchmarks, while Claude Opus 4.5 is better at 5 benchmarks (ARC-AGI v2, GPQA, MMMLU, MMMU (validation), SWE-Bench Verified). Claude Opus 4.5 significantly outperforms across most benchmarks.

On price, Claude Opus 4.5 is roughly 3.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Based on current benchmark, pricing, and model metadata for 2026.

Choose Claude Opus 4

  • you want predictable pricing at $15.00/M input and $75.00/M output

Choose Claude Opus 4.5

  • you want the strongest raw capability — it leads on 5 of 5 shared benchmarks
  • cost matters — it's about 3.0x cheaper per token
  • you want the most recent training data — it shipped Nov 2025

At a glance

The differences that matter most.

Benchmark wins
0 of 5
5 of 5
Input price
$15.00 / M
$5.00 / M
Output price
$75.00 / M
$25.00 / M
Context window
200,000
200,000
Released
May 2025
Nov 2025
License
Proprietary
Proprietary

Performance Benchmarks

Comparative analysis across standard metrics

5 benchmarks

Claude Opus 4 outperforms in 0 benchmarks, while Claude Opus 4.5 is better at 5 benchmarks (ARC-AGI v2, GPQA, MMMLU, MMMU (validation), SWE-Bench Verified).

Claude Opus 4.5 significantly outperforms across most benchmarks.

Wed Aug 26 2026 • llm-stats.com

Arena Performance

Playground indexes and blind preference scores

Pricing Analysis

Price comparison per million tokens

Claude Opus 4.5 costs less

For input processing, Claude Opus 4 ($15.00/1M tokens) is 3.0x more expensive than Claude Opus 4.5 ($5.00/1M tokens).

For output processing, Claude Opus 4 ($75.00/1M tokens) is 3.0x more expensive than Claude Opus 4.5 ($25.00/1M tokens).

In conclusion, Claude Opus 4 is more expensive than Claude Opus 4.5.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Wed Aug 26 2026 • llm-stats.com
Anthropic
Claude Opus 4
Input tokens$15.00
Output tokens$75.00
Best providerAnthropic
Anthropic
Claude Opus 4.5
Input tokens$5.00
Output tokens$25.00
Best providerAnthropic
Notice missing or incorrect data?Start an Issue

Context Window

Maximum input and output token capacity

Both models have the same input context window of 200,000 tokens. Claude Opus 4.5 can generate longer responses up to 64,000 tokens, while Claude Opus 4 is limited to 32,000 tokens.

Anthropic
Claude Opus 4
Input200,000 tokens
Output32,000 tokens
Anthropic
Claude Opus 4.5
Input200,000 tokens
Output64,000 tokens
Wed Aug 26 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Opus 4 and Claude Opus 4.5 support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Claude Opus 4

Text
Images
Audio
Video

Claude Opus 4.5

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Claude Opus 4

Proprietary

Closed source

Claude Opus 4.5

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Opus 4 was released on 2025-05-22, while Claude Opus 4.5 was released on 2025-11-24.

Claude Opus 4.5 is 6 months newer than Claude Opus 4.

Claude Opus 4

May 22, 2025

1.3 years ago

Claude Opus 4.5

Nov 24, 2025

9 months ago

6mo newer

Knowledge Cutoff

When training data ends

Claude Opus 4.5 has a documented knowledge cutoff of 2025-03-31, while Claude Opus 4's cutoff date is not specified.

We can confirm Claude Opus 4.5's training data extends to 2025-03-31, but cannot make a direct comparison without Claude Opus 4's cutoff date.

Claude Opus 4

Claude Opus 4.5

Mar 2025

Provider Availability

Claude Opus 4 is available from Anthropic, Bedrock, Google. Claude Opus 4.5 is available from Anthropic.

Claude Opus 4

anthropic logo
Anthropic
Input Price:Input: $15.00/1MOutput Price:Output: $75.00/1M
bedrock logo
AWS Bedrock
Input Price:Input: $15.00/1MOutput Price:Output: $75.00/1M
google logo
Google
Input Price:Input: $15.00/1MOutput Price:Output: $75.00/1M

Claude Opus 4.5

anthropic logo
Anthropic
Input Price:Input: $5.00/1MOutput Price:Output: $25.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against Claude Opus 4 and Claude Opus 4.5 side-by-side, then vote on the output you prefer.

Claude Opus 4
✓ Preferred
Claude Opus 4.5
Open in Playground

FAQ

Common questions about Claude Opus 4 vs Claude Opus 4.5.

Which is better, Claude Opus 4 or Claude Opus 4.5?

Claude Opus 4.5 significantly outperforms across most benchmarks. Claude Opus 4 is made by Anthropic and Claude Opus 4.5 is made by Anthropic. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Claude Opus 4 compare to Claude Opus 4.5 in benchmarks?

Claude Opus 4 scores MMMLU: 88.8%, TAU-bench Retail: 81.4%, GPQA: 79.6%, MMMU (validation): 76.5%, AIME 2025: 75.5%. Claude Opus 4.5 scores Tau2 Telecom: 98.2%, MMMLU: 90.8%, Tau2 Retail: 88.9%, GPQA: 87.0%, SWE-Bench Verified: 80.9%.

Is Claude Opus 4 cheaper than Claude Opus 4.5?

Claude Opus 4.5 is 3.0x cheaper for input tokens. Claude Opus 4 costs $15.00/M input and $75.00/M output via anthropic. Claude Opus 4.5 costs $5.00/M input and $25.00/M output via anthropic.

What are the context window sizes for Claude Opus 4 and Claude Opus 4.5?

Claude Opus 4 supports 200K tokens and Claude Opus 4.5 supports 200K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Opus 4 and Claude Opus 4.5?

Key differences include input pricing ($15.00 vs $5.00/M). See the full comparison above for benchmark-by-benchmark results.