Gemma 4 12B is open-weights and Apache 2.0 licensed, so “free” here means actually free. There’s no API bill and no subscription. You download the model and run it on your own machine, or try it in a browser tab. The only cost is the hardware you already own.
One thing to know up front: the 12B is built for local and on-device use. Its larger siblings, the 31B and 26B, are the ones Google hosts for free chat in AI Studio. The 12B’s whole pitch is that it runs on a 16GB laptop, so the free paths below are about getting it onto your hardware fast. New to the model? Start with what is Gemma 4 12B for the specs.

Here are six working methods, from a 60-second browser demo to a full local API you can build on.
Quick summary
| Method | What you get | Best for |
|---|---|---|
| Hugging Face Space | Browser chat, zero install | Trying it in a minute |
| Ollama | Local model + OpenAI-compatible API | Developers, one command |
| LM Studio | Local desktop app with a GUI | No terminal needed |
| llama.cpp | Lightweight local API server | Advanced and low-overhead setups |
| HF Transformers | Python, full control, free Colab GPU | Notebooks and fine-tuning |
| Google AI Edge | On-device, mobile | Phones and edge hardware |
Method 1: Try it in your browser (no install)
The fastest way to see Gemma 4 12B is the official demo Space on Hugging Face. No download, no account, no GPU.

- Open the Gemma 4 12B demo Space
- Type a prompt, or upload an image or audio clip
- Read the response
This is the right path for a quick gut check. You can test the multimodal side too, since the Space accepts image and audio input. When you’re ready to build something real, move to one of the local methods below.
Method 2: Ollama (the developer default)
Ollama is the simplest way to run Gemma 4 12B locally and get a working API. One install, one pull, done.

Install Ollama
On macOS or Linux:
curl -fsSL https://ollama.com/install.sh | sh
On Windows, download the installer from ollama.com and run it.
Pull and run the model
ollama pull gemma4:12b
ollama run gemma4:12b
The first command downloads the model (a 4-bit Q4_K_M build by default, around 8GB). The second drops you into an interactive chat. Type /bye to exit.
Use the local API
This is the part developers care about. Ollama serves an OpenAI-compatible REST API at http://localhost:11434. No key, no cloud, no rate limit.
curl http://localhost:11434/v1/chat/completions \
-H "Content-Type: application/json" \
-d '{
"model": "gemma4:12b",
"messages": [
{"role": "user", "content": "Explain how transformers work in two sentences."}
]
}'
Because the endpoint matches the OpenAI format, any SDK or tool that speaks OpenAI works by pointing the base URL at localhost:11434/v1. That includes editors, agent frameworks, and API clients. For an IDE setup pattern, the approach mirrors our DeepSeek V4 in Cursor walkthrough; swap the model string for gemma4:12b.
Useful commands:
ollama listshows downloaded modelsollama psshows what’s runningollama show gemma4:12bprints model details
Method 3: LM Studio (no terminal)
If you’d rather not touch a command line, LM Studio is a desktop app for Windows, macOS, and Linux.
- Download and install LM Studio
- Search for Gemma 4 12B in the model catalog
- Pick a quantization that fits your RAM and download it
- Open the chat tab and start prompting
LM Studio also runs a local server with an OpenAI-compatible endpoint, usually on port 1234, so you get an API without writing any code. It’s the friendliest path for designers, writers, and anyone who wants a chat window over a config file.
Method 4: llama.cpp (lightweight and fast)
llama.cpp runs GGUF models with little overhead and ships its own OpenAI-compatible server.
Install it:
# macOS
brew install llama.cpp
# Windows
winget install llama.cpp
Then start a server pointed at the official GGUF build. Browse the ggml-org/gemma-4 collection on Hugging Face for the exact 12B repo name, then pass it to llama-server:
llama-server -hf ggml-org/gemma-4-12B-it-GGUF
That exposes an OpenAI-compatible API at http://localhost:8080/v1. This path is best when you want minimal dependencies or you’re running on modest hardware. It’s also the engine under several other tools, so learning it pays off.
Method 5: Hugging Face Transformers (full control)
For notebooks, scripts, or fine-tuning, run the model with Transformers in Python. If you don’t have a local GPU, a free Google Colab notebook gives you one.
Install the libraries:
pip install transformers torch accelerate torchvision
# add librosa for audio and video input
pip install librosa
Then load the instruction-tuned model and generate:
from transformers import AutoProcessor, AutoModelForMultimodalLM
MODEL_ID = "google/gemma-4-12B-it"
processor = AutoProcessor.from_pretrained(MODEL_ID)
model = AutoModelForMultimodalLM.from_pretrained(
MODEL_ID,
dtype="auto",
device_map="auto",
)
messages = [
{"role": "system", "content": "You are a helpful assistant."},
{"role": "user", "content": "Write a short joke about saving RAM."},
]
inputs = processor.apply_chat_template(
messages,
tokenize=True,
return_dict=True,
return_tensors="pt",
add_generation_prompt=True,
enable_thinking=False,
).to(model.device)
input_len = inputs["input_ids"].shape[-1]
outputs = model.generate(**inputs, max_new_tokens=1024)
response = processor.decode(outputs[0][input_len:], skip_special_tokens=False)
print(processor.parse_response(response))
Set enable_thinking=True to turn on the step-by-step reasoning mode. To feed an image or audio file, add a content list with {"type": "image", ...} before the text and {"type": "audio", ...} after it. The weights are also on Kaggle if you prefer that source. Full code patterns live in the developer guide.
Method 6: Google AI Edge (on-device and mobile)
To run Gemma 4 12B on a phone or edge device, Google ships the AI Edge stack. The Google AI Edge Gallery app and the LiteRT-LM CLI both run the 12B on-device.
For a local server with LiteRT-LM:
litert-lm import \
--from-huggingface-repo=litert-community/gemma-4-12B-it-litert-lm \
gemma-4-12B-it.litertlm gemma4-12b
litert-lm serve
This is the path for offline mobile assistants and embedded apps where data never leaves the device.
Test your local Gemma 4 12B API with Apidog
Once Gemma 4 12B is running through Ollama or llama.cpp, you have a real HTTP API on your machine. Before you wire it into an app, it helps to poke at it in a proper API client so you know the exact request and response shape. Apidog is built for that.

Here’s a clean setup:
- Download Apidog and create a new HTTP project
- Add a
POSTrequest tohttp://localhost:11434/v1/chat/completions - Set the body to JSON and paste a sample payload:
{
"model": "gemma4:12b",
"messages": [
{"role": "user", "content": "Return a JSON object with two fields: city and country."}
],
"stream": false
}
- Save the base URL as an environment variable so you can switch between Ollama (
:11434) and llama.cpp (:8080) in one click - Add a response assertion to confirm the model returns valid JSON in the
contentfield - Flip
"stream": trueand watch Apidog render the streamed tokens, which is how you’ll confirm streaming works before you build a UI around it
The payoff: you catch a malformed prompt or a wrong field name in Apidog, not three layers deep in your application code. If you’re comparing clients, see our roundup of free online API testing tools and the best Postman alternatives. The same testing flow works for any OpenAI-compatible endpoint, so the habits carry straight over to how to test APIs with Postman style workflows.
Which quantization should you pick?
Gemma 4 12B fits different machines depending on how aggressively it’s compressed:
| Build | Memory needed | Trade-off |
|---|---|---|
| Full precision | ~16GB | Best quality |
| 8-bit | ~14GB | Near-full quality |
| 4-bit (Q4_K_M) | ~8GB | Slight quality drop, runs widely |
Ollama defaults to the 4-bit build, which is why it runs on an 8GB GPU or a 16GB MacBook. If you have the headroom, the 8-bit build gives you a quality bump for a few extra gigabytes.
Which free method should you choose?
A quick decision tree:
- Just curious? The Hugging Face Space demo
- Building software? Ollama, for the one-command local API
- No terminal? LM Studio
- Minimal hardware or dependencies? llama.cpp
- Notebooks or fine-tuning? Transformers, with free Colab for the GPU
- Phone or edge device? Google AI Edge
Most developers land on Ollama for daily use and keep Transformers around for the heavier work.
Tips to get the most out of free local Gemma
- Match the quant to your RAM. A model that swaps to disk runs slowly. The 4-bit build is the safe default.
- Use the thinking mode for hard problems. Set
enable_thinking=Truefor math and multi-step reasoning, leave it off for quick chat to save time. - Keep prompts inside the 256K window. It’s large, but long transcripts and codebases add up.
- Validate requests in Apidog first. Confirm the JSON shape before your app depends on it.
- Compare against other free models. The same local pattern works for Qwen 3.7, MiniMax M3, and Claude Opus 4.8 access paths.
MiniMax’s latest deserves the same treatment — our guide to using MiniMax M2-7 for free lists every current no-cost route.
FAQ
Is Gemma 4 12B really free? Yes. It’s Apache 2.0 open-weights, free to download and run, including commercially. You pay only for the hardware or cloud you run it on.
Do I need a GPU? No, but it helps. The 4-bit build runs on an 8GB GPU or a 16GB unified-memory Mac. On CPU only, it works but runs slowly.
Can I use Gemma 4 12B in Google AI Studio? Not currently. AI Studio hosts the 31B and 26B models for free browser chat. The 12B is built for local and on-device use, so you run it yourself with the methods above.
Does the local API need an API key? No. Ollama and llama.cpp serve the model on localhost with no key. If a tool requires a key field, put any placeholder string; the local server ignores it.
Can I call it from my existing OpenAI code? Yes. Both Ollama and llama.cpp expose OpenAI-compatible endpoints. Point your base URL at http://localhost:11434/v1 (Ollama) or http://localhost:8080/v1 (llama.cpp) and keep your code.
How do I run the image and audio features? Use Transformers, LM Studio, or the AI Edge apps, which support multimodal input. Add image content before your text prompt and audio content after it.
Which is faster, Ollama or llama.cpp? They use the same underlying engine. llama.cpp has less overhead and more tuning flags; Ollama is easier to set up. For most people the difference is small.



