Whether you're a beginner learning your first language or a pro working on a massive codebase, AI code completion tools can help you write better code faster by suggesting lines, functions, and even entire blocks of code based on what you’re doing. It’s like having a helpful pair-programmer sitting beside you—only it never sleeps.
In this post, we’ll break down what these tools are, how they work, and which ones are worth trying today.
What Is AI Code Completion?
AI code completion is a smarter version of autocomplete. It uses artificial intelligence—specifically machine learning models trained on millions (sometimes billions) of lines of open-source code—to predict what you're about to write.
These tools go beyond just finishing a word. They can:
- Suggest entire lines or functions
- Predict logic based on context
- Correct syntax as you type
- Offer documentation or code explanations
- Translate comments into code (and vice versa)
The goal? To help you stay in the zone and reduce mental overhead.
Why Use AI Code Completion?
Here’s why developers across the globe are embracing AI assistants:
- Faster coding: Less typing, fewer mistakes.
- Better learning: Beginners get to see patterns and syntax in real-time.
- Fewer bugs: Suggestions often follow best practices.
- Less context switching: No need to jump between docs or tabs constantly.
Simply put: AI makes coding feel less like a puzzle and more like a flow.
Top AI Code Completion Tools in 2025
Here are some of the most popular and powerful tools developers are using today:
- Codeium – The Best Free Option
If you’re looking for a powerful AI assistant without spending a dime, Codeium is hard to beat.
- Free for individual developers
- Supports 70+ languages
- Works with VS Code, JetBrains, Jupyter, Vim, and more
- Includes AI chat inside your IDE
Codeium is fast, lightweight, and ideal for both beginners and pros. It feels like GitHub Copilot—but without the monthly fee.
- GitHub Copilot – Popular and Powerful
Built by GitHub and OpenAI, Copilot is one of the most widely adopted AI tools for coding. It’s incredibly smart and context-aware, making it great for large projects.
- Integrates with VS Code, JetBrains, Neovim
- Learns from your codebase
- Paid ($10/month), but free for students and open-source contributors
Copilot is ideal if you want deep GitHub integration and the best-in-class suggestions—just be ready to pay.
- Amazon CodeWhisperer – Best for AWS Projects
If you're working with AWS services, CodeWhisperer is a great AI tool tailored for that environment.
- Strong integration with AWS SDKs
- Includes security suggestions
- Free for individual devs
- Works with Java, Python, and JavaScript
Perfect for cloud-native projects and serverless development.
4. Tabnine – Lightweight and Privacy-Focused
Tabnine offers both cloud and local models, which makes it appealing for developers who care about privacy.
- Offline mode for secure environments
- Free tier available
- Supports all major IDEs
- Slightly less powerful than Copilot or Codeium in free mode
If you want privacy and speed over raw power, Tabnine’s a good choice.
Bonus: Use Keploy to Test the Code You Generate
Here’s something most people forget: writing code is only half the battle. Testing it is the real deal.
That’s where Keploy comes in—a free and open-source tool that turns your API traffic into test cases automatically. It works perfectly alongside AI code tools.
Why Keploy?
- Records real API requests and converts them into tests
- Generates mocks for faster local testing
- Supports Go, Java, Python, and more
- Free and open-source
You can pair Keploy with tools like Codeium or Copilot to ensure your AI-generated code doesn’t just work—it stays working.
???? Check out Keploy
How to Choose the Right Tool
Here’s a quick comparison:
| Tool | Best For | Free Tier? |
| Codeium | Powerful, free all-rounder | ✅ |
| GitHub Copilot | Paid, best overall performance | ❌ (students/OSS free) |
| CodeWhisperer | AWS development | ✅ |
| Tabnine | Privacy & offline usage | ✅ |
| Keploy (add-on) | Auto-testing your backend code | ✅ |
Final Thoughts
AI code completion tools are not a replacement for developers—they’re a superpower for developers. Whether you're new to coding or working on your tenth startup, these tools help you code faster, with fewer bugs, and more confidence.
And with tools like Keploy in the mix, you can even automate your testing and take the pain out of QA.
So go ahead—try one out. Let the AI suggest the code, and you focus on building the future.
Read more on https://keploy.io/blog/community/top-5-ai-powered-vs-code-extensions-for-coding-testing-in-2025