Model Comparison

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

Grok 4.5 significantly outperforms across most benchmarks. Phi-3.5-mini-instruct is 30.0x cheaper per token.

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

Grok 4.5 (by xAI) 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.

Grok 4.5 outperforms in 1 benchmarks (GPQA), while Phi-3.5-mini-instruct is better at 0 benchmarks. Grok 4.5 significantly outperforms across most benchmarks.

On price, Phi-3.5-mini-instruct is roughly 30.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Grok 4.5 also accepts a larger context window (500,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose Grok 4.5 if…

  • you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
  • you process long inputs — it offers a 500,000 token context window
  • you want the most recent training data — it shipped Jul 2026

Choose Phi-3.5-mini-instruct if…

  • cost matters — it's about 30.0x cheaper per token
  • you need open weights you can self-host or fine-tune

Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

Grok 4.5 outperforms in 1 benchmarks (GPQA), while Phi-3.5-mini-instruct is better at 0 benchmarks.

Grok 4.5 significantly outperforms across most benchmarks.

Sat Jul 18 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, Grok 4.5 ($2.00/1M tokens) is 20.0x more expensive than Phi-3.5-mini-instruct ($0.10/1M tokens).

For output processing, Grok 4.5 ($6.00/1M tokens) is 60.0x more expensive than Phi-3.5-mini-instruct ($0.10/1M tokens).

In conclusion, Grok 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
Sat Jul 18 2026 • llm-stats.com
xAI
Grok 4.5
Input tokens$2.00
Output tokens$6.00
Best providerxAI
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

Grok 4.5 accepts 500,000 input tokens compared to Phi-3.5-mini-instruct's 128,000 tokens. Only Phi-3.5-mini-instruct specifies output context (128,000 tokens).

xAI
Grok 4.5
Input500,000 tokens
Output- tokens
Microsoft
Phi-3.5-mini-instruct
Input128,000 tokens
Output128,000 tokens
Sat Jul 18 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

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

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

Grok 4.5

Text
Images
Audio
Video

Phi-3.5-mini-instruct

Text
Images
Audio
Video

License

Usage and distribution terms

Grok 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.

Grok 4.5

Proprietary

Closed source

Phi-3.5-mini-instruct

MIT

Open weights

Release Timeline

When each model was launched

Grok 4.5 was released on 2026-07-16, while Phi-3.5-mini-instruct was released on 2024-08-23.

Grok 4.5 is 23 months newer than Phi-3.5-mini-instruct.

Grok 4.5

Jul 16, 2026

2 days ago

1.9yr newer
Phi-3.5-mini-instruct

Aug 23, 2024

1.9 years ago

Knowledge Cutoff

When training data ends

Grok 4.5 has a documented knowledge cutoff of 2026-02-01, while Phi-3.5-mini-instruct's cutoff date is not specified.

We can confirm Grok 4.5's training data extends to 2026-02-01, but cannot make a direct comparison without Phi-3.5-mini-instruct's cutoff date.

Grok 4.5

Feb 2026

Phi-3.5-mini-instruct

—

Provider Availability

Grok 4.5 is available from xAI. Phi-3.5-mini-instruct is available from Azure.

Grok 4.5

xai logo
xAI
Input Price:Input: $2.00/1MOutput Price:Output: $6.00/1M

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

xAI
Larger context window (500,000 tokens)
Supports multimodal inputs
Higher GPQA score (93.0% vs 30.4%)
Microsoft
Less expensive input tokens
Less expensive output tokens
Has open weights

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Grok 4.5 and Phi-3.5-mini-instruct side-by-side, then vote on the output you prefer.

Grok 4.5
✓ Preferred
Phi-3.5-mini-instruct
Open in Playground
AI Model Comparison Table
Feature
xAI
Grok 4.5
Microsoft
Phi-3.5-mini-instruct

FAQ

Common questions about Grok 4.5 vs Phi-3.5-mini-instruct.

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

Grok 4.5 significantly outperforms across most benchmarks. Grok 4.5 is made by xAI 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 Grok 4.5 compare to Phi-3.5-mini-instruct in benchmarks?

Grok 4.5 scores GPQA: 93.0%, Terminal-Bench 2.1: 83.3%, Artificial Analysis Coding Agent Index v1.1: 76.0%, SWE-Bench Pro: 64.7%, AA-Omniscience Index: 63.0%. Phi-3.5-mini-instruct scores GSM8k: 86.2%, ARC-C: 84.6%, RULER: 84.1%, PIQA: 81.0%, OpenBookQA: 79.2%.

Is Grok 4.5 cheaper than Phi-3.5-mini-instruct?

Phi-3.5-mini-instruct is 20.0x cheaper for input tokens. Grok 4.5 costs $2.00/M input and $6.00/M output via xai. Phi-3.5-mini-instruct costs $0.10/M input and $0.10/M output via azure.

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

Grok 4.5 supports 500K 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 Grok 4.5 and Phi-3.5-mini-instruct?

Key differences include context window (500K vs 128K), input pricing ($2.00 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 Grok 4.5 and Phi-3.5-mini-instruct?

Grok 4.5 is developed by xAI and Phi-3.5-mini-instruct is developed by Microsoft.

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