The myth: “AI is expensive”

One of the most common barriers to entry is the perception that using AI costs money. And yes, the best commercial models have a cost. But there’s an enormous range of free options that let you do very interesting things without spending a penny.

Level 1: Free web chats

The easiest way to use AI for free is through the web interfaces of the major models:

ChatGPT (OpenAI): The free version gives access to GPT with a message limit per hour.

Claude (Anthropic): Claude.ai offers a free tier with model access, also with limits.

Gemini (Google): Google AI Studio lets you use Gemini for free.

Limitations: These free tiers don’t give API access. You can chat on the web, but you can’t connect an agent.

Level 2: APIs with a free tier

Some providers offer free APIs with usage limits:

Google AI Studio: Free access to the Gemini API with generous limits. One of the best options for starting without paying.

NVIDIA NIM: Access to several models (including Kimi K2.5) with a free tier. It has rate limits (~40 requests per minute) but is functional for agents with moderate usage.

Groq: Free tier with impressive speed. Ideal for testing and low-volume agents.

Limitations: All have request limits. Free tiers can disappear or change terms at any time.

Level 3: Local models (zero usage cost)

Here comes the most powerful option for a zero budget: running a model on your own computer.

With tools like Ollama, you can download open models and run them locally. Once downloaded, usage is completely free.

Hardware requirements:

For small models (1-3B parameters): 8GB RAM, any modern CPU. Slow but functional responses.

For medium models (7-8B parameters): 16GB RAM, better with a dedicated GPU. Acceptable speed for interactive use.

For large models (13-70B parameters): 32-64GB RAM or GPU with plenty of VRAM. We’re talking serious hardware here.

Advantages: Zero cost, total privacy, works without internet.

Disadvantages: You need decent hardware, local models are less powerful than the best commercial models.

The smart combination

Most people who build agents combine several options:

Expensive model for important decisions: Claude or GPT for tasks requiring maximum quality.

Free model for volume: NVIDIA NIM or a local model for routine, repetitive tasks.

This strategy lets you have a powerful agent without going broke.

Practical summary

For someone starting out who wants to spend zero:

  1. Start with Google AI Studio (free Gemini API) for your first agent
  2. Install Ollama with a 7-8B model to experiment locally
  3. Sign up for NVIDIA NIM as a backup provider

With these three options you have a functional agent without paying anything.

Key concepts today

  • Free API tiers: Google AI Studio, NVIDIA NIM, Groq — free access with limits
  • Local models (Ollama): Download the model and run it on your hardware. Zero usage cost
  • Smart combination: Expensive model for quality + cheap/free model for volume
  • Cost is per token: You pay for each word processed, not for a subscription

Next lesson: Local models — running an LLM on your computer with Ollama.