ModPackQT Desktop

Download ModPackQT Desktop

Run ModPackQT Desktop on your computer to connect local Modbus devices and run simulations.

Download forarchitecture

macOS — Apple Silicon

Big Sur or later

All releases

See it in action

Zero firewall changes

ModPackQT Desktop opens an outbound tunnel — no inbound ports needed.

End-to-end secure

All traffic is encrypted. Your Modbus hardware stays on the local network.

Multi-site ready

Run ModPackQT Desktop on each computer. Manage every site from a single account.

What is ModPackQT Desktop?

ModPackQT Desktop is a lightweight app that runs on each field computer or engineering workstation. It bridges your local Modbus devices — connected via serial port (RTU) or local network (TCP) — to the ModPackQT cloud, so you can monitor and control them from anywhere.

Do I need ModPackQT Desktop?

The browser and the desktop app serve different purposes.

Browser only
No install
  • View & graph live Modbus data
  • Manage connection profiles
  • Virtual device sandbox (API)
  • AI-assisted register mapping
  • Connect to local Modbus TCP/IP device
  • Connect via RS-485 / serial (RTU)
  • Run scheduled poll bots locally
  • Works without internet after setup
Recommended
With ModPackQT Desktop
  • View & graph live Modbus data
  • Manage connection profiles
  • Virtual device sandbox (API)
  • AI-assisted register mapping
  • Connect to local Modbus TCP/IP device
  • Connect via RS-485 / serial (RTU)
  • Run scheduled poll bots locally
  • Works without internet after setup

How it works — 3 steps

  1. 1

    Install & start

    Download for Windows, Mac, or Linux. Runs as a small background service — no window stays open.

  2. 2

    It connects up

    Opens a secure outbound tunnel to modpackqt.com. No firewall changes or port forwarding needed.

  3. 3

    Use your browser

    Everything looks the same. You'll see a 'Desktop connected' badge and your real device data flows in.

System Requirements

Minimum

1–2 slaves, manual master reads

  • Dual-core 2.0 GHz (i3 / Ryzen 3)
  • 4 GB RAM
  • Windows 10+, macOS 10.15+, Ubuntu 20.04+
Recommended

Recommended

Multiple slaves + bots + master polling

  • Quad-core 2.5 GHz+ (i5 / Ryzen 5)
  • 8 GB RAM
  • Windows 10/11, macOS 12+, Ubuntu 22.04+

Heavy Use

Many slaves + MQTT + bots + live graphing

  • Quad-core 3.0 GHz+ (i7 / Ryzen 7)
  • 16 GB RAM
  • Windows 10/11, macOS 13+

Performance may be unstable if:

  • Your machine is below the minimum spec (especially under 4 GB RAM)
  • You are running more slaves, bots, or master connections than your tier supports
  • Heavy applications (SCADA, HMIs, IDEs) are running alongside ModPackQT Desktop

Google Chrome is required for Modbus RTU via serial port. Other browsers do not support the WebSerial API.

Quick start

1

Download & install

Get the ModPackQT Desktop app for your operating system.

2

Launch it

It starts on port 8502 by default and shows a running indicator.

3

Open ModPackQT Settings

The ModPackQT Desktop URL auto-populates — no token or manual steps needed.

4

Add a Cloud Gateway Key

In Settings → Cloud Gateways, click "Add Gateway", name it, and paste the key into the app.

macOS Installation Guide

macOS requires a few extra steps because ModPackQT Desktop is not yet notarized with Apple. Follow the steps below.

1

Drag to Applications

Open the downloaded .dmg file, then drag the ModPackQT Desktop icon into the Applications folder.

2

Security warning appears

Apple will show a "Not Opened" warning the first time. Click Done — do NOT click "Move to Trash".

3

Right-click to open

Go to Applications, right-click ModPackQT Desktop → Open. Click Open on the next dialog. It will launch normally from then on.

Why does macOS block it?

Apple's Gatekeeper blocks apps that haven't been notarized through the Apple Developer Program. ModPackQT Desktop is open-source and safe — right-clicking and choosing Open bypasses this one-time check.

ModPackQT Desktop is open source

Contributions welcome on GitHub.