Imagine an AI that can answer questions about your own documents, contracts, study notes, or research, without a single file ever leaving your machine. That is the promise of local RAG: it pulls relevant snippets from your files and feeds them to an on-device AI, so the answers are grounded in your material and your data stays private.
Quick Answer
Local RAG (retrieval-augmented generation) feeds snippets from your own documents into an AI running on your computer so it can answer questions about them, with every file staying on your machine. The AI retrieves the relevant passages first, then generates its answer from them. Nothing is sent to the cloud.
How RAG Actually Works, Step by Step
RAG splits the job into two stages, and understanding that split makes the whole idea click.
First, retrieval. Your documents are broken into small chunks and converted into a searchable index. When you ask a question, the system finds the chunks most relevant to it, the passages most likely to contain the answer.
Second, generation. Those retrieved passages are handed to the AI language model along with your question. The model writes its answer using that supplied text as the source, rather than relying only on what it memorised during training.
The result is an answer grounded in your actual files, which sharply reduces the made-up responses that pure chatbots are prone to.
What Makes It "Local"
In a cloud setup, your question and your documents travel to a remote server. In a local RAG setup, both the retrieval index and the language model run on your own hardware. Your files never leave the device.
That distinction matters for anyone handling sensitive material: legal documents, medical records, financial data, or proprietary research. For SA professionals working under data-protection obligations, keeping everything on-device sidesteps the question of where your data went entirely. It also means the system works offline, with no subscription and no dependence on a connection.
What You Need to Run It
Running an AI model locally asks more of your machine than browsing a cloud chatbot. The language model needs to fit in memory and run fast enough to feel responsive, so a few things matter:
- A capable CPU and, ideally, a GPU with enough video memory to accelerate the model.
- Generous system RAM, since models and indexes both consume memory.
- An NPU on newer AI-ready systems, which speeds up on-device inference efficiently.
Smaller models run on modest hardware; larger, more capable ones want a proper GPU. The current crop of AI-ready machines is built with exactly this kind of on-device work in mind, and the AI PC range at Evetech is a well-stocked starting point for finding systems that handle local models comfortably.
Local RAG vs a Cloud Chatbot
The trade-offs are straightforward. A cloud chatbot is effortless to start with and runs on huge models, but your data leaves your control and you pay ongoing fees. Local RAG keeps everything private and offline, runs with no subscription, and answers strictly from your own documents, at the cost of needing capable hardware and a little setup. For private, document-grounded answers, local RAG wins; for casual general questions, a cloud assistant is simpler. To see how complete AI-capable machines are currently priced and configured, the PC best sellers at Evetech offer a useful cross-section of what South Africans are actually buying.
Frequently Asked Questions
What does RAG stand for?
RAG stands for retrieval-augmented generation. It means the AI first retrieves relevant snippets from a set of documents, then uses those snippets to generate a grounded answer rather than relying only on its training.
Is local RAG completely private?
Yes, when it is genuinely local. Both the search index and the language model run on your own device, so your documents and questions never travel to a remote server. It also works without an internet connection.
Do I need a powerful PC to run local RAG?
You need more than for a cloud chatbot. Smaller models run on modest machines, but larger, more capable models benefit from a good GPU, plenty of RAM, and ideally an NPU on AI-ready systems.
How is local RAG different from ChatGPT?
A cloud assistant sends your data to remote servers and answers from its general training. Local RAG keeps everything on your machine and answers specifically from your own documents, making it private and grounded in your files.
Can it work with my existing files?
Yes. That is the point. You point local RAG at your documents, it indexes them, and then you can ask questions answered directly from that material, all on your own hardware.