Gemini 3.1 Pro vs Gemini 1.5 Pro
Compare pricing, context windows, and strengths for Gemini 3.1 Pro by Google and Gemini 1.5 Pro by Google - and see how to put either to work in Appaca.
Gemini 3.1 Pro
Google's most advanced reasoning Gemini model, built for complex multimodal problem-solving, software engineering, and long-horizon agentic workflows.
View Gemini 3.1 ProGemini 1.5 Pro
A next-generation multimodal model with breakthrough long-context capability up to 1M tokens and strong reasoning across text, code, audio, video, and images.
View Gemini 1.5 ProGemini 3.1 Pro vs Gemini 1.5 Pro at a glance
Specs and pricing side by side, from the Appaca AI models directory.
| Spec | Gemini 3.1 Pro | Gemini 1.5 Pro |
|---|---|---|
| Provider | ||
| Model type | Text | Text |
| Context window | 1.05M tokens | 1M tokens |
| Input price | $4 / 1M tokens | $3.5 / 1M tokens |
| Output price | $18 / 1M tokens | $7 / 1M tokens |
| Status | Current | Current |
How Gemini 3.1 Pro and Gemini 1.5 Pro differ
What the numbers mean in practice when choosing between Gemini 3.1 Pro and Gemini 1.5 Pro.
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Gemini 1.5 Pro is 13% cheaper on input tokens ($3.5 vs $4 per million), which adds up quickly in document-heavy workloads.
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Gemini 1.5 Pro is 61% cheaper on output tokens ($7 vs $18 per million) - the bigger factor for tools that generate long documents.
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Context windows are close: Gemini 3.1 Pro handles 1.05M tokens and Gemini 1.5 Pro handles 1M tokens.
Strengths side by side
Where each model shines, according to benchmarks and provider positioning.
Gemini 3.1 Pro
1. Google's most advanced reasoning Gemini model
- Designed to solve complex problems across multimodal inputs, including text, audio, images, video, PDFs, and full code repositories.
- Google highlights improved software engineering behavior, better agentic performance, and stronger usability in domains like finance and spreadsheets.
2. Large multimodal context with substantial output room
- Supports a 1,048,576 token input context window for large repositories, long documents, and multi-source workflows.
- Allows up to 65,536 output tokens for longer answers, plans, and code generations.
3. More efficient thinking with expanded controls
- Improves token efficiency and reasoning performance across use cases.
- Adds the
MEDIUMthinking_leveloption to better balance cost, speed, and quality.
4. Strong support for production agents
- Supports grounding with Google Search, code execution, function calling, structured outputs, context caching, RAG, and chat completions.
- Also offers a custom-tools endpoint tuned for agentic workflows that mix bash-like tools with custom code tools.
Gemini 1.5 Pro
1. Breakthrough long-context window up to 1,000,000 tokens
- Can process 1 hour of video, 11 hours of audio, 700k+ words, or 100k+ lines of code in a single prompt.
- Supports advanced retrieval, reasoning, summarization, and cross-document tasks.
- Achieves 99% retrieval accuracy on 1M-token Needle-In-A-Haystack tests.
2. Strong multimodal reasoning across video, audio, images, and text
- Can analyze long videos (e.g., full silent films), track events, infer causality, and identify small details.
- Handles large complex documents like manuals, transcripts, and books.
3. High-performance reasoning and problem solving
- Comparable to Gemini 1.0 Ultra across many benchmarks.
- Excels at code reasoning, multi-step explanations, and large-scale codebase analysis.
4. Advanced code understanding and generation
- Performs problem-solving on codebases exceeding 100,000 lines.
- Capable of cross-file reasoning, debugging guidance, API comprehension, and generating structured code improvements.
5. Efficient Mixture-of-Experts (MoE) architecture
- Activates only relevant expert pathways per input.
- Enables faster training, lower latency, and more efficient serving.
- Dramatically improves scalability and inference speed.
6. Exceptional in-context learning capabilities
- Learns new tasks directly from long prompts without fine-tuning.
- Demonstrated by learning to translate a low-resource language (Kalamang) from a grammar manual.
7. High-fidelity multimodal understanding
- Reads, analyzes, and reasons about long PDFs, code repositories, images, and videos together.
- Enables new classes of applications: legal analysis, scientific review, codebase audits, long-form content generation, etc.
8. Safety and reliability first
- Undergoes extensive ethics, safety testing, and red-teaming.
- Improved representational safety and reduced hallucinations compared to previous generations.
9. Available for developers and enterprises
- Accessible via AI Studio and Vertex AI.
- Supports future pricing tiers for expanded context windows.
- Designed for real enterprise-scale workloads.
10. Widely capable mid-size model
- Positioned between Gemini Pro and Gemini Ultra generations.
- Well-balanced: reasoning, multimodality, long-context, and speed.
Use Gemini 3.1 Pro or Gemini 1.5 Pro - or both
Appaca is the AI workspace for operators. Build internal tools and AI co-workers powered by Gemini 3.1 Pro or Gemini 1.5 Pro - connected to your real data and ready for your whole team. No code, no deployment.
Describe it, and it's built
Tell the Appaca agent the internal tool you need and it builds a working app powered by Gemini 3.1 Pro or Gemini 1.5 Pro. No code, no API keys, no deployment.
Switch models without rebuilding
Start on Gemini 3.1 Pro, test the same tool on Gemini 1.5 Pro, and keep whichever performs better - the rest of your app stays exactly as it is.
Automated for the whole team
Schedule tools to run on autopilot - daily digests, weekly reports, real-time triggers - and share them with your whole team from one workspace.
Describe it, and it's built
Tell the Appaca agent what your team needs and it builds a working app powered by Gemini 3.1 Pro or Gemini 1.5 Pro - connected to the tools you already use.







Related comparisons
See how Gemini 3.1 Pro and Gemini 1.5 Pro stack up against other models in the directory.
FAQs
Gemini 1.5 Pro is generally cheaper: $3.5 input / $7 output per million tokens, versus $4 / $18 for Gemini 3.1 Pro. Actual cost depends on how many tokens your workload reads and writes.
Gemini 3.1 Pro has the larger context window at 1.05M tokens, compared to 1M tokens for Gemini 1.5 Pro. A larger window means the model can consider more text at once - useful for long contracts, codebases, or months of records.
It depends on the job. Compare the pricing, context window, and strengths above against your workload - and remember the choice isn't permanent. In Appaca you can build a tool on Gemini 3.1 Pro, test the same tool on Gemini 1.5 Pro, and switch at any time without rebuilding anything.
Yes. Appaca is a no-code AI workspace: describe the internal tool your team needs and the Appaca agent builds it as a working app powered by Gemini 3.1 Pro, Gemini 1.5 Pro, or any other model in the directory - with a built-in database, team access, and integrations. No API keys to wire up and nothing to deploy.
Build AI tools with Gemini 3.1 Pro or Gemini 1.5 Pro
Describe the tool your team needs and get a working app powered by the model you choose - with a built-in database, team access, and integrations. No code, no deployment.