AI reasoning has reached new heights with Google's Gemini 3 Deep Think and OpenAI's GPT-5.2 Thinking Mode. Both models excel at complex problem-solving, but they approach reasoning differently. This comparison breaks down their capabilities, performance differences, and best use cases to help you choose the right model for your projects.
The race for advanced AI reasoning has intensified with two powerful contenders: Gemini 3 Deep Think and GPT-5.2 Thinking Mode. Both models represent significant leaps in how AI approaches complex problems, but they differ in their reasoning strategies, multimodal capabilities, and optimal use cases.
If you're trying to decide which model to use for your next project, this comparison will help you make an informed choice based on real performance differences.
Traditional language models generate responses quickly but sometimes lack depth in logical reasoning. Both Gemini 3 Deep Think and GPT-5.2 Thinking Mode address this limitation by spending more time "thinking" through problems before responding.
Gemini 3 Deep Think uses a flexible thinking level system that lets you choose between low and high reasoning intensity. This gives you control over how much processing power gets devoted to problem-solving versus speed.
GPT-5.2 Thinking Mode takes a different approach with five distinct reasoning effort levels: none, low, medium, high, and xhigh. This granular control allows you to fine-tune the balance between response speed and reasoning depth.
The key difference lies in how these models allocate computational resources. Gemini 3 focuses on multimodal understanding alongside reasoning, while GPT-5.2 emphasizes pure reasoning capability with optional image analysis.
One of the most significant distinctions between these models is their approach to handling different input types.
Gemini 3 Deep Think accepts:
This makes Gemini 3 the clear choice for projects involving multimedia content. You can analyze video content, transcribe long audio files, or process multiple images in a single request.
GPT-5.2 Thinking Mode supports:
While GPT-5.2 handles text and images well, it doesn't process video or audio natively. If your project requires analyzing multimedia content, Gemini 3 offers more flexibility.
Speed matters when you're running AI at scale or need real-time responses. Here's how these models compare:
Gemini 3 Deep Think delivers:
GPT-5.2 Thinking Mode offers:
The verbosity control in GPT-5.2 is particularly useful because it prevents the model from over-explaining when you need concise answers. Gemini 3 doesn't have this feature, which can lead to longer responses than necessary.
Both models excel at different types of reasoning tasks.
Gemini 3 Deep Think shines in:
GPT-5.2 Thinking Mode excels at:
The choice between them often comes down to your specific use case. If you're working with text and images only, GPT-5.2's focused approach might yield better results. For projects involving video or audio analysis, Gemini 3 is your only option.
Let's look at how these models perform in practical scenarios.
Both models can generate high-quality articles, but with different strengths:
When writing technical documentation:
For automated customer support systems:
In research applications:
Understanding token usage helps optimize your AI spending.
Gemini 3 Deep Think allocates tokens differently based on thinking level. Higher thinking levels consume more tokens during the reasoning process, but the default maximum of 65,535 tokens gives you substantial output capacity.
GPT-5.2 Thinking Mode requires careful attention to max_completion_tokens. At higher reasoning efforts (high and xhigh), much of your token budget goes to internal reasoning. You might need to increase max_completion_tokens to avoid empty responses.
This is a critical difference: GPT-5.2 can use all your tokens for reasoning and return nothing, while Gemini 3 balances reasoning and output more automatically.
Choose Gemini 3 Deep Think if you need:
Choose GPT-5.2 Thinking Mode if you need:
Consider both when:
Both models represent significant advances in AI reasoning capabilities. The competition between Google and OpenAI pushes both companies to innovate faster.
We're likely to see future improvements in:
The gap between these models will probably narrow as both companies iterate on their technology.
Ready to test these models yourself? PicassoIA provides access to both Gemini 3 Deep Think and GPT-5.2 Thinking Mode through a user-friendly interface.
Step 1: Access the Model
Visit the GPT-5.2 Advanced Language Model page on PicassoIA.
Step 2: Configure Your Prompt
Enter your text prompt in the main input field. You can use either a simple prompt or structure it as messages for conversational flows.
Example prompt structure:
Write a technical analysis of quantum computing developments in 2025
Step 3: Set Reasoning Effort
Choose your reasoning_effort level based on task complexity:
Step 4: Adjust Verbosity
Set verbosity to control response length:
Step 5: Optional Configuration
If needed, configure additional parameters:
Step 6: Generate and Review
Click generate and wait for the model to complete its reasoning process. Higher reasoning efforts take longer but produce more thoughtful responses.
Step 1: Navigate to Gemini 3
Go to the Gemini 3 Pro page on PicassoIA.
Step 2: Enter Your Prompt
Type your prompt in the text field. This is the only required parameter.
Example prompt:
Analyze this product video and create a detailed feature comparison
Step 3: Add Multimodal Inputs (Optional)
Upload your media files:
Step 4: Configure Thinking Level
Select your thinking_level:
Step 5: Fine-Tune Generation Settings
Adjust optional parameters if needed:
Step 6: Generate Results
Click generate and the model will process your inputs. Multimodal requests take longer depending on file sizes.
| Feature | Gemini 3 Deep Think | GPT-5.2 Thinking Mode |
|---|---|---|
| Reasoning Levels | 2 (low, high) | 5 (none, low, medium, high, xhigh) |
| Multimodal Input | Images, Videos, Audio | Images only |
| Verbosity Control | No | Yes (low, medium, high) |
| Max Output Tokens | 65,535 (default) | Configurable |
| Best For | Multimedia analysis | Text-based reasoning |
| Speed | Fast to moderate | Variable by effort level |
Both Gemini 3 Deep Think and GPT-5.2 Thinking Mode represent impressive advances in AI reasoning. Your choice should be based on your specific needs:
If you work with multimedia content or need flexible reasoning without complex configuration, Gemini 3 Deep Think offers a streamlined approach with powerful multimodal capabilities.
If you need granular control over reasoning depth and work primarily with text, GPT-5.2 Thinking Mode provides more fine-tuning options and potentially faster responses at lower reasoning levels.
The best approach might be to test both models with your specific use cases. PicassoIA makes it easy to experiment with both models and compare results side by side.
Start exploring both models today and see which one delivers better results for your projects. The future of AI reasoning is here, and you have two excellent options to choose from.
