Ever wondered which AI model is the best fit for your Copilot project? You're not alone. Picking the right one can feel somewhat mysterious—each has its strengths, but which one is just right for your task?

With models that prioritize speed, depth, or a balance of both, it helps to know what each one brings to the table. Let’s break it down together. 👇

The TL;DR

💳 Balance between cost and performance:
Go with GPT-4o or Claude 3.5 Sonnet.

🪙 Fast, lightweight tasks:
o3-mini or Claude 3.5 Sonnet are your buddies.

💎 Deep reasoning or complex debugging:
Think GPT-4.5, o1, or Claude 3.7 Sonnet.

🖼️ Multimodal inputs (like images):
Check out Gemini 2.0 Flash or GPT-4o.

Let’s talk models:

🏎️ Speedy

o3-mini: The speed demon 😈
Fast, efficient, and cost-effective, o3-mini is ideal for simple coding questions and quick iterations. If you’re looking for a no-frills model, this is the one.

✅ Use it for:

• Quick prototyping.
• Explaining code snippets.
• Learning new programming concepts.
• Generating boilerplate code.

🚫 When to skip:

For complex, multi-file tasks or deep reasoning, you’ll want to move up to GPT-4.5 or o1. If you want to be more expressive, try another model.

⚖️ Balanced

GPT-4o and GPT-4.1: The all-rounder 🌎
These are your go-to models for general tasks. Need fast responses? Check. Want to work with text and images? Double check. GPT-4o and GPT-4.1 are like the Swiss Army knives of AI models: flexible, dependable, and cost-efficient.

✅ Use them for:

• Explaining code blocks.
• Writing comments or docs.
• Generating small, reusable snippets.
• Multilingual prompts.

🚫 When to skip:

If you’re diving into complex logic or multi-step reasoning, call in the big guns like GPT-4.5 or Claude 3.7 Sonnet.

Claude 3.5 Sonnet: The budget-friendly helper 😊
Need solid performance but watching your costs? Claude 3.5 Sonnet is like a dependable sidekick. It’s great for everyday coding tasks without burning through your monthly usage.

✅ Use it for:

• Writing documentation.
• Answering language-specific questions.
• Generating code snippets.

🚫 When to skip:

For tasks requiring multi-step reasoning or detailed architecture planning, Claude 3.7 Sonnet or GPT-4.5 might be better options.

🧠 Thoughtful

GPT-4.5: The thinker 💭
Got a tricky problem? Whether you’re debugging multi-step issues or crafting full-on systems architectures, GPT-4.5 thrives on nuance and complexity.

✅ Use it for:

• Writing detailed README files.
• Generating full functions or multi-file solutions.
• Debugging complex errors.
• Making architectural decisions.

🚫 When to skip:

If you’re just iterating quickly or concerned about costs, GPT-4o might get the job done faster and cheaper.

o1: The deep diver 🥽
This model is perfect for tasks that need precision and logic. Whether you’re optimizing performance-critical code or refactoring a messy codebase, o1 excels in breaking down problems step by step.

✅ Use it for:

• Code optimization.
• Debugging complex systems.
• Writing structured, reusable code.
• Summarizing logs or benchmarks.

🚫 When to skip:

If you’re prototyping or working on lightweight tasks, a faster model like o3-mini might be a better fit. Something like GPT-4o or Gemini 2.0 Flash responds better (if not faster) for the lightweight stuff, too.

Claude 3.7 Sonnet: The architect 🏠
This one’s the power tool for large, complex projects. From multi-file refactoring to feature development across front end and back end, Claude 3.7 Sonnet shines when context and depth matter most.

✅ Use it for:

• Refactoring large codebases.
• Planning complex architectures.
• Designing algorithms.
• Combining high-level summaries with deep analysis.

🚫 When to skip:

If you’re just iterating quickly or working on basic tasks, Claude 3.5 Sonnet or GPT-4o might be more efficient. It might over-engineer and apply unnecessary complexity to your smaller s.

🖼️ Multimodal

Gemini 2.0 Flash: The visual thinker 🤔
Got visual inputs like UI mockups or diagrams? Gemini 2.0 Flash lets you bring images into the mix, making it a great choice for front-end prototyping or layout debugging.

✅ Use it for:

• Analyzing diagrams or screenshots.
• Debugging UI layouts.
• Generating code snippets.
• Getting design feedback.

🚫 When to skip:

If you’re working on complex algorithms or multi-step reasoning, other models like GPT-4.5 or Claude 3.7 Sonnet are better equipped.

So… which do I choose?

Here’s the rule of thumb: match the model to the task. Practice really does make perfect, and as you work with different models, it’ll become clearer which ones work best for different tasks. The more I’ve personally used certain models, the more I’ve learned, “oh, I should switch for this particular task,” and “this one will get me there.”

Good luck, go forth, and happy coding!

Learn more about AI models

✨ This newsletter was written by Cassidy Williams and produced by Gwen Davis. ✨

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