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GPT-6 Luna vs Phi 4

GPT-6 Luna leads the LLM Stats Score 44.5 to 5.4. Phi 4 is 2.3x cheaper per token.

OpenAI · Microsoft · Updated for 2026

Which is better?

GPT-6 Luna leads the overall LLM Stats Score 44.5 to 5.4, ranking #41 overall.

On price, Phi 4 is roughly 2.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-6 Luna also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose GPT-6 Luna

  • overall performance matters — it scores 44.5 and ranks #41 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you process long inputs — it offers a 1,050,000 token context window
  • you want the most recent training data — it shipped Sep 2026

Choose Phi 4

  • cost matters — it's about 2.3x cheaper per token
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Core performance indexes
44.5
#41
5.4
#302
40.0
#58
6.5
#293
31.4
#47
3.4
#223
Cost, coverage & limits
Benchmark wins
Input price
$0.10 / M
$0.07 / M
Output price
$0.50 / M
$0.14 / M
Context window
1,050,000
16,384

Individual benchmarks

5 reported for GPT-6 Luna · 13 for Phi 4

No common benchmarks found

GPT-6 Luna and Phi 4don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Phi 4 costs less

For input processing, GPT-6 Luna ($0.10/1M tokens) is 1.4x more expensive than Phi 4 ($0.07/1M tokens).

For output processing, GPT-6 Luna ($0.50/1M tokens) is 3.6x more expensive than Phi 4 ($0.14/1M tokens).

In conclusion, GPT-6 Luna is more expensive than Phi 4.*

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

Lowest available price from all providers
Wed Sep 23 2026 • llm-stats.com
OpenAI
GPT-6 Luna
Input tokens$0.10
Output tokens$0.50
Best providerOpenAI
Microsoft
Phi 4
Input tokens$0.07
Output tokens$0.14
Best providerDeepinfra
Notice missing or incorrect data?Start an Issue

Context Window

Maximum input and output token capacity

GPT-6 Luna accepts 1,050,000 input tokens compared to Phi 4's 16,384 tokens. GPT-6 Luna can generate longer responses up to 128,000 tokens, while Phi 4 is limited to 16,384 tokens.

OpenAI
GPT-6 Luna
Input1,050,000 tokens
Output128,000 tokens
Microsoft
Phi 4
Input16,384 tokens
Output16,384 tokens
Wed Sep 23 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

GPT-6 Luna supports multimodal inputs, whereas Phi 4 does not.

GPT-6 Luna can handle both text and other forms of data like images, making it suitable for multimodal applications.

GPT-6 Luna

Text
Images
Audio
Video

Phi 4

Text
Images
Audio
Video

License

Usage and distribution terms

GPT-6 Luna is licensed under a proprietary license, while Phi 4 uses MIT.

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

GPT-6 Luna

Proprietary

Closed source

Phi 4

MIT

Open weights

Release Timeline

When each model was launched

GPT-6 Luna was released on 2026-09-22, while Phi 4 was released on 2024-12-12.

GPT-6 Luna is 22 months newer than Phi 4.

GPT-6 Luna

Sep 22, 2026

0 days ago

1.8yr newer
Phi 4

Dec 12, 2024

1.8 years ago

Knowledge Cutoff

When training data ends

GPT-6 Luna has a knowledge cutoff of 2026-05-18, while Phi 4 has a cutoff of 2024-06-01.

GPT-6 Luna has more recent training data (up to 2026-05-18), making it potentially better informed about events through that date compared to Phi 4 (2024-06-01).

GPT-6 Luna

May 2026

1.9 yr newer
Phi 4

Jun 2024

Provider Availability

GPT-6 Luna is available from OpenAI. Phi 4 is available from DeepInfra.

GPT-6 Luna

openai logo
OpenAI
Input Price:Input: $0.10/1MOutput Price:Output: $0.50/1M

Phi 4

deepinfra logo
Deepinfra
Input Price:Input: $0.07/1MOutput Price:Output: $0.14/1M
* 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 GPT-6 Luna and Phi 4 side-by-side, then vote on the output you prefer.

GPT-6 Luna
✓ Preferred
Phi 4
Open in Playground

FAQ

Common questions about GPT-6 Luna vs Phi 4.

Which is better, GPT-6 Luna or Phi 4?

GPT-6 Luna leads the LLM Stats Score 44.5 to 5.4. GPT-6 Luna is made by OpenAI and Phi 4 is made by Microsoft. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does GPT-6 Luna compare to Phi 4 in benchmarks?

GPT-6 Luna scores DeepSWE 1.1: 66.6%, OSWorld 2.0: 52.7%, Agents' Last Exam: 50.9%, FrontierCode 1.1: 42.4%, AutomationBench v1.0.6: 20.7%. Phi 4 scores MMLU: 84.8%, HumanEval+: 82.8%, HumanEval: 82.6%, MGSM: 80.6%, MATH: 80.4%.

Is GPT-6 Luna cheaper than Phi 4?

Phi 4 is 1.4x cheaper for input tokens. GPT-6 Luna costs $0.10/M input and $0.50/M output via openai. Phi 4 costs $0.07/M input and $0.14/M output via deepinfra.

What are the context window sizes for GPT-6 Luna and Phi 4?

GPT-6 Luna supports 1.1M tokens and Phi 4 supports 16K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT-6 Luna and Phi 4?

Key differences include LLM Stats Score (44.5 vs 5.4), context window (1.1M vs 16K), input pricing ($0.10 vs $0.07/M), multimodal support (yes vs no), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-6 Luna and Phi 4?

GPT-6 Luna is developed by OpenAI and Phi 4 is developed by Microsoft.