Tools · 2026-10-22

Gerty: a private ChatGPT alternative that sets itself up on your Mac

Gerty is a Mac app that runs AI directly on your computer, so you can chat with an assistant without sending your data to the internet.

✨ How much space the setup takes

On a Mac with 16 GB of memory, the first download for Gerty Max is about 18 GB in total. The app itself is 340 MB, and the rest is AI models chosen for that specific computer.

About 8.5 GB goes to chatting. This includes Gemma 4 E4B, which can also read pictures, and a small model that routes your messages. Another 9 GB is for creating and editing images.

Gerty shows the required size before anything downloads, so there are no surprises.

📌 What you can leave out

The picture model is optional if you only want chat. Gerty Max is the full bundle for the fastest setup with all features. Other bundles exist too, such as Gerty Thinking, which focuses only on the assistant part.

People with little disk space can start with Gerty Thinking and add Max later. The discussion does not state this explicitly, but it follows from how the bundles are described.

🔹 Searching your own documents

Gerty can search your files by meaning, not only by exact words. This requires a separate 330 MB model, which downloads the first time you use this feature.

🔸 Who it is for

A local assistant is a good option for people who do not want to send their notes and documents to outside services. The authors also noted that the website has a separate section on the app's limits, so it is worth reading before installing.

Sources: 🔗 Product Hunt — AI