Model Comparison

Claude Opus 4.5 vs Phi-3.5-mini-instructWhich is better in 2026?

Claude Opus 4.5 significantly outperforms across most benchmarks. Phi-3.5-mini-instruct is 100.0x cheaper per token.

Verdict: Claude Opus 4.5 vs Phi-3.5-mini-instruct — which is better?

Claude Opus 4.5 (by Anthropic) and Phi-3.5-mini-instruct (by Microsoft) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

Claude Opus 4.5 outperforms in 2 benchmarks (GPQA, MMMLU), while Phi-3.5-mini-instruct is better at 0 benchmarks. Claude Opus 4.5 significantly outperforms across most benchmarks.

On price, Phi-3.5-mini-instruct is roughly 100.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Claude Opus 4.5 also accepts a larger context window (200,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose Claude Opus 4.5 if…

  • you want the strongest raw capability — it leads on 2 of 2 shared benchmarks
  • you process long inputs — it offers a 200,000 token context window
  • you want the most recent training data — it shipped Nov 2025

Choose Phi-3.5-mini-instruct if…

  • cost matters — it's about 100.0x cheaper per token
  • you need open weights you can self-host or fine-tune
Want to compare interactively?Try the playground

Performance Benchmarks

Comparative analysis across standard metrics

2 benchmarks

Claude Opus 4.5 outperforms in 2 benchmarks (GPQA, MMMLU), while Phi-3.5-mini-instruct is better at 0 benchmarks.

Claude Opus 4.5 significantly outperforms across most benchmarks.

Sun Jun 07 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Phi-3.5-mini-instruct costs less

For input processing, Claude Opus 4.5 ($5.00/1M tokens) is 50.0x more expensive than Phi-3.5-mini-instruct ($0.10/1M tokens).

For output processing, Claude Opus 4.5 ($25.00/1M tokens) is 250.0x more expensive than Phi-3.5-mini-instruct ($0.10/1M tokens).

In conclusion, Claude Opus 4.5 is more expensive than Phi-3.5-mini-instruct.*

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

Lowest available price from all providers
Sun Jun 07 2026 • llm-stats.com
Anthropic
Claude Opus 4.5
Input tokens$5.00
Output tokens$25.00
Best providerAnthropic
Microsoft
Phi-3.5-mini-instruct
Input tokens$0.10
Output tokens$0.10
Best providerAzure
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Claude Opus 4.5 accepts 200,000 input tokens compared to Phi-3.5-mini-instruct's 128,000 tokens. Phi-3.5-mini-instruct can generate longer responses up to 128,000 tokens, while Claude Opus 4.5 is limited to 64,000 tokens.

Anthropic
Claude Opus 4.5
Input200,000 tokens
Output64,000 tokens
Microsoft
Phi-3.5-mini-instruct
Input128,000 tokens
Output128,000 tokens
Sun Jun 07 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Claude Opus 4.5 supports multimodal inputs, whereas Phi-3.5-mini-instruct does not.

Claude Opus 4.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Opus 4.5

Text
Images
Audio
Video

Phi-3.5-mini-instruct

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Opus 4.5 is licensed under a proprietary license, while Phi-3.5-mini-instruct uses MIT.

License differences may affect how you can use these models in commercial or open-source projects.

Claude Opus 4.5

Proprietary

Closed source

Phi-3.5-mini-instruct

MIT

Open weights

Release Timeline

When each model was launched

Claude Opus 4.5 was released on 2025-11-24, while Phi-3.5-mini-instruct was released on 2024-08-23.

Claude Opus 4.5 is 15 months newer than Phi-3.5-mini-instruct.

Claude Opus 4.5

Nov 24, 2025

6 months ago

1.3yr newer
Phi-3.5-mini-instruct

Aug 23, 2024

1.8 years ago

Knowledge Cutoff

When training data ends

Claude Opus 4.5 has a documented knowledge cutoff of 2025-03-31, while Phi-3.5-mini-instruct'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 Phi-3.5-mini-instruct's cutoff date.

Claude Opus 4.5

Mar 2025

Phi-3.5-mini-instruct

—

Provider Availability

Claude Opus 4.5 is available from Anthropic. Phi-3.5-mini-instruct is available from Azure.

Claude Opus 4.5

anthropic logo
Anthropic
Input Price:Input: $5.00/1MOutput Price:Output: $25.00/1M

Phi-3.5-mini-instruct

azure logo
Azure
Input Price:Input: $0.10/1MOutput Price:Output: $0.10/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic
Larger context window (200,000 tokens)
Supports multimodal inputs
Higher GPQA score (87.0% vs 30.4%)
Higher MMMLU score (90.8% vs 55.4%)
Microsoft
Less expensive input tokens
Less expensive output tokens
Has open weights

Detailed Comparison

AI Model Comparison Table
Feature
Anthropic
Claude Opus 4.5
Microsoft
Phi-3.5-mini-instruct

FAQ

Common questions about Claude Opus 4.5 vs Phi-3.5-mini-instruct.

Which is better, Claude Opus 4.5 or Phi-3.5-mini-instruct?

Claude Opus 4.5 significantly outperforms across most benchmarks. Claude Opus 4.5 is made by Anthropic and Phi-3.5-mini-instruct is made by Microsoft. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Claude Opus 4.5 compare to Phi-3.5-mini-instruct in benchmarks?

Claude Opus 4.5 scores Tau2 Telecom: 98.2%, MMMLU: 90.8%, Tau2 Retail: 88.9%, GPQA: 87.0%, SWE-Bench Verified: 80.9%. Phi-3.5-mini-instruct scores GSM8k: 86.2%, ARC-C: 84.6%, RULER: 84.1%, PIQA: 81.0%, OpenBookQA: 79.2%.

Is Claude Opus 4.5 cheaper than Phi-3.5-mini-instruct?

Phi-3.5-mini-instruct is 50.0x cheaper for input tokens. Claude Opus 4.5 costs $5.00/M input and $25.00/M output via anthropic. Phi-3.5-mini-instruct costs $0.10/M input and $0.10/M output via azure.

What are the context window sizes for Claude Opus 4.5 and Phi-3.5-mini-instruct?

Claude Opus 4.5 supports 200K tokens and Phi-3.5-mini-instruct supports 128K 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 4.5 and Phi-3.5-mini-instruct?

Key differences include context window (200K vs 128K), input pricing ($5.00 vs $0.10/M), multimodal support (yes vs no), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 4.5 and Phi-3.5-mini-instruct?

Claude Opus 4.5 is developed by Anthropic and Phi-3.5-mini-instruct is developed by Microsoft.

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