The best AI for coding in 2025 (including a new winner – and what not to use)

I’ve been around technology long enough that very little excites me, and even less surprises me. But shortly after OpenAI’s ChatGPT was released, I asked it to write a WordPress plugin for my wife’s e-commerce site. When it did, and the plugin worked, I was indeed surprised.

That was the beginning of my deep exploration into chatbots and AI-assisted programming. Since then, I’ve subjected 14 large language models (LLMs) to four real-world tests.

Also: Only 8% of Americans would pay extra for AI, according to ZDNET-Aberdeen research

Unfortunately, not all chatbots can code alike. It’s been a little over two years since that first test, and even now, four of the 13 LLMs I tested can’t create working plugins.

The short version

In this article, I’ll show you how each LLM performed against my tests. There are now five chatbots I recommend you use. 

Two of them, ChatGPT Plus and Perplexity Pro, cost $20 per month each. The free versions of the same chatbots do well enough that you could probably get by without paying. Two other recommended products are from Google and Microsoft. Google’s Gemini Pro 2.5 is free, but you’re limited to so few queries that you really can’t use it without paying. 

Also: I tested 10 AI content detectors – and these 5 correctly identified AI text every time

Microsoft has several Copilot licenses, which can get pricey, but I used the free version with surprisingly good results. The final one, Claude 4 Sonnet, is the free version of Claude. Oddly enough, the free version beat the paid-for version, so we’re not recommending Claude 4 Opus.

But the rest, whether free or paid, are not so great. I won’t risk my programming projects with them or recommend that you do, until their performance improves.

I’ve written lots about using AIs to help with programming. Unless it’s a small, simple project like my wife’s plugin, AIs can’t write entire apps or programs. But they excel at writing a few lines and are not bad at fixing code.

Rather than repeat everything I’ve written, go ahead and read this article: How to use ChatGPT to write code.

If you want to understand my coding tests, why I’ve chosen them, and why they’re relevant to this review of the 13 LLMs, read this article: How I test an AI chatbot’s coding ability.

The AI coding leaderboard

Let’s start with a comparative look at how the chatbots performed, as of this installment of our best-of roundup:

Next, let’s look at each chatbot individually. I’m back up to discussing 14 chatbots, because we’re splitting out Claude 4 Sonnet and Claude 4 Opus as separate tests. GPT-4 is no longer included since OpenAI has sunsetted that LLM. Ready? Let’s go.

Chatbots to avoid for programming help

I tested 13 LLMs, and nine passed most of my tests this time around. The other chatbots, including a few pitched as great for programming, only passed one of my tests.

Also: The five biggest mistakes people make when prompting an AI

I’m mentioning them here because people will ask, and I did test them thoroughly. Some of these bots are fine for other work, so I’ll point you to their general reviews if you’re curious about their functionality.

DeepSeek R1

Unlike DeepSeek V3, the advanced reasoning version, DeepSeek R1, did not showcase its reasoning capabilities in our programming tests. Unusually, the new failure area was one that’s not all that hard, even for a basic AI — the regular expression code for our string function test.  

Also: I tested DeepSeek’s R1 and V3 coding skills – and we’re not all doomed (yet)

But that’s why we are running these real-world tests. It’s never clear where an AI will hallucinate or just plain fail, and before you go believing all the hype about DeepSeek R1 taking the crown away from ChatGPT, run some programming tests. So far, while I’m impressed with the much-reduced resource utilization and the open-source nature of the product, its coding quality output is inconsistent.

GitHub Copilot

GitHub’s Copilot integrates quite seamlessly with VS Code. The AI makes asking for coding help quick and productive, especially when working in context. That’s why it’s so disappointing that the code the AI outputs is often very wrong.

Also: I put GitHub Copilot’s AI to the test – and it just might be terrible at writing code

I can’t, in good conscience, recommend you use the GitHub Copilot extensions for VS Code. I’m concerned that the temptation will be too great to insert blocks of code without sufficient testing — and that GitHub Copilot’s produced code is not ready for production use. Try again next year.

Claude 4 Opus

In a completely baffling turn of events, the paid-for version of the Claude 4 model, Opus, failed half of my tests. What makes this result baffling is that the free version, Claude 4 Sonnet, passed them all. I don’t know what to say apart from AI can be weird.

Also: Anthropic’s free Claude 4 Sonnet aced my coding tests – but its paid Opus model somehow didn’t

Meta AI

Meta AI is Facebook’s general-purpose AI. As you can see above, it failed three of our four tests. 

Also: 15 ways AI saved me time at work in 2024 – and how I plan to use it in 2025

The AI generated a nice user interface, but with zero functionality. It also found my annoying bug, which is a fairly serious challenge. Given the specific knowledge required to find the bug, I was surprised that the AI choked on a simple regular expression challenge. But it did.

Meta Code Llama

Meta Code Llama is Facebook’s AI explicitly designed for coding help. It’s something you can download and install on your server. I tested the AI running on a Hugging Face AI instance.

Also: Can Meta AI code? I tested it against Llama, Gemini, and ChatGPT – it wasn’t even close

Weirdly, even though both Meta AI and Meta Code Llama choked on three of four of my tests, they choked on different problems. AIs can’t be counted on to give the same answer twice, but this result was a surprise. We’ll see if that changes over time.

But I like [insert name here]. Does this mean I have to use a different chatbot?

Probably not. I’ve limited my tests to day-to-day programming tasks. None of the bots has been asked to talk like a pirate, write prose, or draw a picture. In the same way we use different productivity tools to accomplish specific tasks, feel free to choose the AI that helps you complete the task at hand.

The only issue is if you’re on a budget and are paying for a pro version. Then, find the AI that does most of what you want, so you don’t have to pay for too many AI add-ons.

It’s only a matter of time

The results of my tests were pretty surprising, especially given the significant improvements by Microsoft and Google. However, this area of innovation is improving at warp speed, so we’ll be back with updated tests and results over time. Stay tuned.

Have you used any of these AI chatbots for programming? What has your experience been? Let us know in the comments below.

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