Model Comparison
GPT-4 Turbo vs GPT-5.6 SolWhich is better in 2026?
GPT-5.6 Sol significantly outperforms across most benchmarks. GPT-5.6 Sol is 1.3x cheaper per token.
Verdict: GPT-4 Turbo vs GPT-5.6 Sol — which is better?
GPT-4 Turbo (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-4 Turbo outperforms in 0 benchmarks, while GPT-5.6 Sol is better at 1 benchmark (GPQA). GPT-5.6 Sol significantly outperforms across most benchmarks.
On price, GPT-5.6 Sol is roughly 1.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-5.6 Sol also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.
Choose GPT-4 Turbo if…
- you want predictable pricing at $10.00/M input and $30.00/M output
Choose GPT-5.6 Sol if…
- you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
- cost matters — it's about 1.3x cheaper per token
- you process long inputs — it offers a 1,050,000 token context window
- you want the most recent training data — it shipped Jul 2026
Performance Benchmarks
Comparative analysis across standard metrics
GPT-4 Turbo outperforms in 0 benchmarks, while GPT-5.6 Sol is better at 1 benchmark (GPQA).
GPT-5.6 Sol significantly outperforms across most benchmarks.
Arena Performance
Human preference votes
Pricing Analysis
Price comparison per million tokens
For input processing, GPT-4 Turbo ($10.00/1M tokens) is 2.0x more expensive than GPT-5.6 Sol ($5.00/1M tokens).
For output processing, GPT-4 Turbo ($30.00/1M tokens) costs the same as GPT-5.6 Sol ($30.00/1M tokens).
In conclusion, GPT-4 Turbo is more expensive than GPT-5.6 Sol.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-5.6 Sol accepts 1,050,000 input tokens compared to GPT-4 Turbo's 128,000 tokens. GPT-5.6 Sol can generate longer responses up to 128,000 tokens, while GPT-4 Turbo is limited to 4,096 tokens.
Input Capabilities
Supported data types and modalities
GPT-5.6 Sol supports multimodal inputs, whereas GPT-4 Turbo does not.
GPT-5.6 Sol can handle both text and other forms of data like images, making it suitable for multimodal applications.
GPT-4 Turbo
GPT-5.6 Sol
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
GPT-4 Turbo was released on 2024-04-09, while GPT-5.6 Sol was released on 2026-07-09.
GPT-5.6 Sol is 27 months newer than GPT-4 Turbo.
Apr 9, 2024
2.3 years ago
Jul 9, 2026
1 weeks ago
2.2yr newerKnowledge Cutoff
When training data ends
GPT-4 Turbo has a knowledge cutoff of 2023-12-31, 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-4 Turbo (2023-12-31).
Dec 2023
Feb 2026
2.2 yr newerProvider Availability
GPT-4 Turbo is available from Azure, OpenAI. GPT-5.6 Sol is available from OpenAI.
GPT-4 Turbo
GPT-5.6 Sol
Outputs Comparison
Key Takeaways
GPT-4 Turbo
View detailsOpenAI
No standout differentiators in the data we have for this pair.
GPT-5.6 Sol
View detailsOpenAI
Detailed Comparison
Interactive Arena
Judge for yourself.
Run your own prompts against GPT-4 Turbo and GPT-5.6 Sol side-by-side, then vote on the output you prefer.
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FAQ
Common questions about GPT-4 Turbo vs GPT-5.6 Sol.