Chat with a Local AI
In this tutorial you’ll install Open WebUI, pull a language model through Ollama, and have your first conversation with a locally-running AI chatbot — completely offline and private.
Step 1: Prerequisites
You’ll need Thumper-Run installed on your machine. If you haven’t done that yet, follow the installation steps in the First Image tutorial (Step 1 only) and come back here.
- Thumper-Run installed and running
- At least 8 GB of free disk space (for the app + default model)
- An internet connection for the initial download (after that, everything runs offline)
Step 2: Install Open WebUI
Open WebUI is a polished chat interface that connects to Ollama for local language models. Thumper-Run bundles both together so you don’t need to configure anything manually.
- In the catalog, find Open WebUI (or type "open webui" in the search bar)
- Click the Install button on the app card
- Watch the console as pip installs dependencies — this takes 2–5 minutes
[INFO] Creating virtual environment...[INFO] Installing open-webui (pip)...Collecting open-webuiDownloading open_webui-0.6.x.tar.gz (42 MB)Installing collected packages: open-webui[INFO] Installation complete.
Test it: The app card should now show a Launch button instead of Install.
Step 3: Pull a Model
Ollama manages language models for you. When you launch Open WebUI for the first time, Thumper-Run starts Ollama in the background and pulls a default model automatically.
- Click Launch on the Open WebUI card
- Watch the console — Ollama starts first, then the model downloads
- The default model (Llama 3.2 3B) is ~2 GB and takes 1–3 minutes to download
- Once the model is ready, the status changes to "Running"
[INFO] Starting Ollama server...[INFO] Ollama listening on 127.0.0.1:11434[INFO] Pulling model: llama3.2:3bpulling manifest...pulling dde5aa3fc5ff... 100% 2.0 GBverifying sha256 digestwriting manifest[INFO] Model ready.
Test it: In the Thumper-Run dashboard, click the running app to open its detail view, then select the Console tab in the sidebar. You should see "Model ready" with no errors. Back in the Open WebUI chat interface, the chat input box becomes active (no longer grayed out) when the model is loaded and ready.
Step 4: Chat
Your local chatbot is ready. Time to talk to it!
- Type a message in the chat box and press Enter — try something like "Explain quantum computing in simple terms"
- Watch the response stream in token by token, just like a cloud AI
- Ask a follow-up question — the model remembers the conversation context
- Click New Chat in the sidebar to start a fresh conversation
Response speed depends on your hardware:
| Hardware | Approx. Speed | Notes |
|---|---|---|
| RTX 4090 | ~80 tok/s | Near-instant responses |
| RTX 3060 | ~30 tok/s | Smooth conversational speed |
| CPU only | ~5 tok/s | Usable but noticeably slower |
Test it: Ask the model "What is 2+2?" — you should get a response within a few seconds on any hardware.
How Fast Is Fast?
In practical terms, an RTX 4090 generates a full paragraph (~100 tokens) in about 1.5 seconds. An RTX 3060 takes about 4 seconds for the same response. On CPU only, expect around 20 seconds. These times are for the default 3B model — larger models (7B, 13B) are proportionally slower but more capable.
Step 5: Customize
Open WebUI has a number of features that let you tailor the chatbot to your needs.
System Prompts
Set a system prompt to give the model a persistent personality or role. For example: "You are a helpful coding assistant who explains concepts with examples." Click the settings icon in the chat header to edit.
Temperature
Temperature controls randomness. Lower values (0.1–0.3) give focused, deterministic answers. Higher values (0.7–1.0) produce more creative and varied responses. Adjust in the model parameters panel.
Switch Models
Use the model dropdown at the top of the chat to switch between installed models. Larger models (7B, 13B) are more capable but slower; smaller models (1B, 3B) are faster and use less memory.
Upload Documents
Drag and drop a PDF, text file, or code file into the chat to ask questions about it. Open WebUI chunks the document and feeds relevant sections to the model as context (RAG).
Sample System Prompts
# Coding assistantYou are a senior software engineer. Explain concepts withrunnable code examples. Use Rust when possible. Be concise.# Creative writing coachYou are a creative writing mentor. Give constructive feedbackon prose, suggest improvements, and explain writing techniqueswith examples from published fiction.
Troubleshooting
| Problem | Cause | Fix |
|---|---|---|
| Connection refused | Port 11434 already in use | Run lsof -i :11434 to find the process, then systemctl stop ollama (if system-installed) or kill <PID> |
| Model not responding | Model still loading into memory | Wait 10–30 seconds; check the console tab for progress |
| Very slow responses | Model too large for VRAM; running on CPU | Switch to a smaller model (1B or 3B) or close other GPU apps |
Key Takeaways
- Everything runs locally — your conversations never leave your machine
- Ollama manages model downloads and serving automatically
- GPU accelerates responses but is not required
- System prompts let you customize the model’s behavior per-chat
- You can switch models at any time without restarting
Next Steps
- Try image generation — follow the First Image tutorial
- Browse more models — see model management for installing larger or specialized models
- Create your own model pack — follow the Model Pack tutorial
- Try a different LLM engine — see LLM Engines for llama.cpp and cloud API alternatives
- Try the AI agent — install apps, debug issues, and generate code with natural language
- Read the full documentation for advanced features like API keys and multi-device sync