Here’s the straight comparison. Gemma 3 vs Gemma 4: Google’s Gemma 4 is the newer open model, and it’s a real step up — especially if you want a free, local brain for an AI agent. Here’s how the two compare and which you should use.
The short answer: Gemma 4 for almost everything, especially agentic work.
Last updated: July 2026.
Key takeaways
Gemma 4 is the upgrade — better reasoning, more agentic, and near the quality of models twice its size.
Gemma 4 12B is laptop-ready (about 16GB VRAM), free, open source and works offline.
For a free local Hermes brain, Gemma 4 is the clear pick over Gemma 3.
Gemma 3 was a solid, capable open model in its day. Gemma 4 is the newer generation, and it’s better where it counts for agents: stronger reasoning, more genuinely agentic behaviour, and impressive quality for its size. If you’re choosing today, Gemma 4 is the one.
Gemma 3
Gemma 4
Generation
Previous
Current
Agentic reasoning
Capable
Noticeably stronger
Quality for size
Good
Near models 2x its size
Runs locally
Yes
Yes — 12B is laptop-ready (~16GB VRAM)
Free & open source
Yes
Yes
What’s New in Gemma 4
The standout of Gemma 4 is how much quality it packs into a small, free, local model. The 12B version lands near the quality of models twice its size, uses advanced reasoning, and is designed to behave agentically — so it can actually plan and use tools when you plug it into an agent, not just chat.
It’s laptop-ready at around 16GB of VRAM, open source, and — because it runs locally — it works offline, which the big cloud models can’t.
Gemma 3 vs Gemma 4 for Agents (Hermes)
This is where the gap matters most. When you use a model as the brain of an agent like Hermes, agentic reasoning is everything — and Gemma 4 is meaningfully better at it than Gemma 3. It follows tool-use loops more reliably and holds up better on real agent tasks.
For any new setup, use Gemma 4. Gemma 3 still works if it’s already running in your stack and you don’t need the extra reasoning, but there’s little reason to start with the older generation when Gemma 4 is free, laptop-ready and clearly stronger.
Want it free but don’t have the hardware? You can run Gemma 4 via a free API too — see my best free AI model guide.
How to Run Gemma 4 (Free)
Download Ollama and pull the latest Gemma 4 model.
Run the launch command to start your agent with Gemma 4.
Or use the Hermes web UI — pick Ollama + Gemma 4 on the Models page, no terminal needed.
Point it at a task and let it work — locally and free.
No powerful machine? Run Gemma 4 through a free API instead — details in my free AI model guide.
What You Can Do With Gemma 4
Because Gemma 4 is agentic, it doesn’t just answer — it acts. Plug it into an agent and it’ll run a morning brief, triage your inbox, research a topic, review your notes, or build small tools and apps — all on a schedule, and all free once it’s running locally.
Is Gemma 4 Good Enough on Its Own?
Be realistic: Gemma 4 is a small, free local model, so a frontier model like Opus 4.8 is far more powerful, and Gemma isn’t amazing at long-form writing. The smart move is to use it as a fast, free sub-agent for smaller tasks, paired with a stronger main model for the heavy lifting — the best of both worlds without burning tokens.
Get It Set Up
The whole free local-brain setup — Gemma 4 running as a Hermes sub-agent alongside a frontier main model — is pre-built in the Agent OS inside the AI Profit Boardroom.
