Model Comparison

GPT-5.5 vs GPT-5.6 SolWhich is better in 2026?

GPT-5.6 Sol significantly outperforms across most benchmarks. GPT-5.5 and GPT-5.6 Sol cost the same.

Verdict: GPT-5.5 vs GPT-5.6 Sol — which is better?

GPT-5.5 (by OpenAI) and GPT-5.6 Sol (by OpenAI) 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.

GPT-5.5 outperforms in 1 benchmarks (MMMU-Pro), while GPT-5.6 Sol is better at 8 benchmarks (BrowseComp, FrontierMath, GDPval-AA, GPQA, Graphwalks BFS >128k, MRCR v2 (8-needle), SWE-Bench Pro, Toolathlon). GPT-5.6 Sol significantly outperforms across most benchmarks.

Choose GPT-5.5 if…

  • you want predictable pricing at $5.00/M input and $30.00/M output

Choose GPT-5.6 Sol if…

  • you want the strongest raw capability — it leads on 8 of 9 shared benchmarks
  • you want the most recent training data — it shipped Jul 2026

Performance Benchmarks

Comparative analysis across standard metrics

9 benchmarks

GPT-5.5 outperforms in 1 benchmarks (MMMU-Pro), while GPT-5.6 Sol is better at 8 benchmarks (BrowseComp, FrontierMath, GDPval-AA, GPQA, Graphwalks BFS >128k, MRCR v2 (8-needle), SWE-Bench Pro, Toolathlon).

GPT-5.6 Sol significantly outperforms across most benchmarks.

Wed Jul 22 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

For input processing, GPT-5.5 ($5.00/1M tokens) costs the same as GPT-5.6 Sol ($5.00/1M tokens).

For output processing, GPT-5.5 ($30.00/1M tokens) costs the same as GPT-5.6 Sol ($30.00/1M tokens).

In conclusion, GPT-5.5 and GPT-5.6 Sol cost the same.*

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

Lowest available price from all providers
Wed Jul 22 2026 • llm-stats.com
OpenAI
GPT-5.5
Input tokens$5.00
Output tokens$30.00
Best providerOpenAI
OpenAI
GPT-5.6 Sol
Input tokens$5.00
Output tokens$30.00
Best providerOpenAI
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 1,050,000 tokens. Both models can generate responses up to 128,000 tokens.

OpenAI
GPT-5.5
Input1,050,000 tokens
Output128,000 tokens
OpenAI
GPT-5.6 Sol
Input1,050,000 tokens
Output128,000 tokens
Wed Jul 22 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both GPT-5.5 and GPT-5.6 Sol support multimodal inputs.

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

GPT-5.5

Text
Images
Audio
Video

GPT-5.6 Sol

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.

GPT-5.5

Proprietary

Closed source

GPT-5.6 Sol

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5.5 was released on 2026-04-23, while GPT-5.6 Sol was released on 2026-07-09.

GPT-5.6 Sol is 3 months newer than GPT-5.5.

GPT-5.5

Apr 23, 2026

2 months ago

GPT-5.6 Sol

Jul 9, 2026

1 weeks ago

2mo newer

Knowledge Cutoff

When training data ends

GPT-5.5 has a knowledge cutoff of 2025-12-01, while GPT-5.6 Sol has a cutoff of 2026-02-16.

GPT-5.6 Sol has more recent training data (up to 2026-02-16), making it potentially better informed about events through that date compared to GPT-5.5 (2025-12-01).

GPT-5.5

Dec 2025

GPT-5.6 Sol

Feb 2026

2 mo newer

Provider Availability

GPT-5.5 is available from OpenAI. GPT-5.6 Sol is available from OpenAI.

GPT-5.5

openai logo
OpenAI
Input Price:Input: $5.00/1MOutput Price:Output: $30.00/1M

GPT-5.6 Sol

openai logo
OpenAI
Input Price:Input: $5.00/1MOutput Price:Output: $30.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

OpenAI
Higher MMMU-Pro score (83.2% vs 83.0%)
OpenAI
Higher BrowseComp score (90.4% vs 84.4%)
Higher FrontierMath score (89.0% vs 35.4%)
Higher GDPval-AA score (58.3% vs 37.8%)
Higher GPQA score (94.6% vs 93.6%)
Higher Graphwalks BFS >128k score (90.7% vs 45.4%)
Higher MRCR v2 (8-needle) score (91.5% vs 74.0%)
Higher SWE-Bench Pro score (64.6% vs 58.6%)
Higher Toolathlon score (58.0% vs 55.6%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against GPT-5.5 and GPT-5.6 Sol side-by-side, then vote on the output you prefer.

GPT-5.5
✓ Preferred
GPT-5.6 Sol
Open in Playground
AI Model Comparison Table
Feature
OpenAI
GPT-5.5
OpenAI
GPT-5.6 Sol

FAQ

Common questions about GPT-5.5 vs GPT-5.6 Sol.

Which is better, GPT-5.5 or GPT-5.6 Sol?

GPT-5.6 Sol significantly outperforms across most benchmarks. GPT-5.5 is made by OpenAI and GPT-5.6 Sol is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does GPT-5.5 compare to GPT-5.6 Sol in benchmarks?

GPT-5.5 scores Tau2 Telecom: 98.0%, ARC-AGI: 95.0%, GPQA: 93.6%, ARC-AGI v2: 85.0%, GDPval-MM: 84.9%. GPT-5.6 Sol scores Connectors: 100.0%, Capture-the-Flag Challenges (Internal): 96.7%, HealthBench Consensus: 95.5%, GPQA: 94.6%, MRCR v2 (8-needle): 91.5%.

Is GPT-5.5 cheaper than GPT-5.6 Sol?

Both models cost $5.00 per million input tokens.

What are the context window sizes for GPT-5.5 and GPT-5.6 Sol?

GPT-5.5 supports 1.1M tokens and GPT-5.6 Sol supports 1.1M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

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