Free to compile. Pro to ship.

Two ways to use Serial Studio, one project format. Start with whichever fits your work today and switch when you need to.

Open source

GPLv3 source

Compile it yourself

Free
License
GPLv3
Binary
You build from source
Commercial use
Permitted under GPLv3
Production use
Permitted under GPLv3
  • Serial/UART, TCP/UDP, Bluetooth LE
  • 15+ widgets: plots, gauges, GPS, FFT, compass, data grids
  • JavaScript and Lua frame parsers
  • Quick Plot and the visual Project Editor
  • CSV export and playback
  • TCP API and MCP server
  • Community support on GitHub
View source on GitHub

Requires an open-source Qt and a GPL-compliant project around it.

Recommended

Pro license

Official binary, full feature set

$19 /mo · or $699 lifetime
License
Commercial
Binary
Official installers for every platform
Commercial use
Permitted
Production use
Permitted
  • Everything in the free build, plus:
  • MQTT, Modbus, CAN with DBC, OPC UA, S7, EtherNet/IP, IEC 104
  • Audio, Raw USB, HID, Process I/O
  • 3D, XY, Waterfall and ImageView widgets, plus the scripted Painter
  • MDF4 read/write, session database and HTML/PDF reports
  • AI Assistant with bring-your-own-key or local LLM
  • Output controls, multi-device projects, operator deployments
  • Email support
Try Pro free for 14 days

Starts when you first use a Pro feature. No card required.

Can't afford a license yet? Contribute to the project and earn one.

Pick the plan that fits

Every plan includes the full Pro feature set. The difference is how many seats and how you pay.

Yearly

$179/yr

For a single engineer. Save 21% compared to paying monthly.

  • All Pro features
  • 3 device activations
  • Commercial & private use
  • All updates while active
  • Email support
  • Cancel any time
Get yearly

Prefer monthly? $19 / month

Lifetime

$699

One-time payment for a single engineer. Pays back after 37 months.

  • All Pro features, forever
  • All future Pro releases included
  • No subscription, no renewals
  • 3 device activations
  • Commercial & private use
  • Can be activated offline (air-gapped)
  • Email support
Buy lifetime

Small Business

$39/mo

For a team up to 10. Or $349 / year (save 25%).

  • All Pro features, every seat
  • 10 device activations across the team
  • Commercial & private use
  • Operator deployments
  • Centralized licensing, one invoice
  • Email support
Get team plan

More than 10 seats? Ask for a quote.

Test Stand

$1,900

One-time, for industrial test stands & equipment. 20 offline devices at $95 each, forever.

Get test stand

Need a different device count, or buying as a company? Start here.

Free vs Pro feature comparison

Every difference between the two builds, for anyone who wants the exact list before deciding.

CapabilityFree (GPL)Pro
Data sources
Serial/UART (USB, RS-232, RS-485)✓✓
TCP / UDP networking✓✓
Bluetooth Low Energy✓✓
MQTT publish / subscribe×✓
Modbus RTU & TCP×✓
CAN Bus + DBC import×✓
OPC UA (encrypted sessions, tag browsing)×✓
Siemens S7 (S7comm)×✓
EtherNet/IP (Allen-Bradley CIP)×✓
IEC 60870-5-104×✓
Audio input (FFT, waterfall)×✓
Raw USB (libusb)×✓
HID devices (hidapi)×✓
Process I/O (child stdout, named pipes)×✓
Visualization & widgets
Line/multi plot, FFT, bar, gauge, compass✓✓
Accelerometer, gyroscope, GPS map✓✓
Data grid, LED panel, terminal✓✓
3D Plot, XY Plot, Waterfall (spectrogram)×✓
ImageView (live camera/image feed)×✓
Painter (user-scripted Canvas2D)×✓
Plot Sweep / Trigger mode (oscilloscope-style)×✓
Data flow & automation
Built-In frame decoders (code-free, compiled C++)✓✓
JavaScript / Lua frame parsers✓✓
Binary (Direct) parser mode✓✓
Control Loop automation (setup / loop)✓✓
Per-dataset transforms (EMA, scaling, calibration)✓✓
CSV export & playback✓✓
MDF4 / MF4 export and playback×✓
Session database (SQLite Explorer)×✓
Session reports (HTML / PDF)×✓
File transfer (XMODEM / YMODEM / ZMODEM)×✓
Output widgets (buttons, sliders, knobs)×✓
Multi-device projects×✓
Integration & AI
TCP API (320+ commands)✓✓
gRPC server (typed protobuf streaming)✓✓
MCP server for AI hosts✓✓
AI Assistant (BYOK / local LLM)×✓
Modbus register-map importer×✓
CAN DBC importer (auto-generates projects)×✓
Operator deployments (--runtime, locked builds)×✓
Licensing
LicenseGPLv3Commercial
Closed-source / commercial use×✓
Official precompiled binaries×✓
Email support×✓

See the full license agreement for the precise legal terms.

Before you decide

The questions visitors ask most often about licensing and the trial.

Can I use the free build commercially if I compile from source?

Yes. A build compiled from source with GPL modules only is GPLv3 software, and the GPLv3 permits commercial use, including internal business tools and revenue-generating workflows. It excludes the Pro features; businesses that need those, the official binaries, or email support buy a Pro license or evaluate with the 14-day trial.

See the full license for the exact terms.

What happens after the 14-day trial?

Serial Studio falls back to the free tier instead of locking you out. The free features (Serial/UART, TCP/UDP, BLE, the standard widgets, scripting and CSV recording) keep working in the official binary with no time limit for personal, educational and open-source use. From there you can:

· Activate a Pro license to keep the full feature set and use Serial Studio commercially, or
· Compile the GPLv3 source for a free build that also permits commercial use.

The trial runs once per release on each machine. Reinstalls, VMs and clock changes do not reset it; a new release starts a new 14-day trial.

Fourteen days suits a single engineer. If you are evaluating for a plant, lab or test floor where the decision moves at the speed of procurement, ask for an extended evaluation.

When does the 14-day trial start?

Not at install. Serial Studio always opens in the free tier, and the trial starts the first time you use a Pro feature, such as a Pro driver, a Pro widget or a multi-device project. Until then the clock does not run, so you can set up a project with the free features first and start the trial when you are ready to evaluate Pro.

Can I compile Pro from source if I have a license?

The official Pro binary is the supported way to use Pro. Buying a Pro license covers it end to end, including the Qt commercial components it links against. No second purchase needed.

Compiling Pro from source is possible for licensees, but it requires your own Qt commercial license on top of the Serial Studio Pro license, plus build instructions you would need to request directly. Practically, that path costs more than buying Pro outright, and it is not how most users should approach this. If you need a specific Pro behavior to change, email me or open a pull request. It is almost always faster and cheaper than self-compiling.

Note that a Qt commercial license alone does not grant any right to compile Pro features. The Pro modules are governed by the Serial Studio commercial license.

What counts as a "device activation"?

One activation equals one running install of Serial Studio. The Pro plans (Monthly, Yearly and Lifetime) include 3 activations, Small Business includes 10, and Test Stand includes 20.

You can deactivate a machine with the Deactivate button in the License Management dialog (About → Manage License) and reactivate elsewhere. Activations are tied to a hardware fingerprint, not to a user account.

What is the Test Stand plan, and can it run offline?

Test Stand is a one-time, lifetime license built for industrial test benches, production equipment and other machines that stay in service for years. It is $1,900 for 20 device activations ($95 per device, perpetual), with commercial, OEM and integrator use included.

Every seat can be activated offline: export a device file from the air-gapped machine, generate a signed license file, and import it. No internet connection, no phone-home, no subscription to renew. Compared with the Small Business annual plan for the same 20 seats, it pays for itself in under three years, then costs nothing for the rest of the equipment's life.

Need a different device count or a purchase order? Email me for a quote.

How long does the Lifetime plan last?

It is the lifetime of Serial Studio. One payment, all future Pro updates, no renewals.

It pays back versus monthly after about 37 months, or versus annual after about 4 years.

Can I switch plans or get a refund?

Plans can be changed at any time from the Lemon Squeezy customer portal.

Refunds are available within 14 days of purchase if Pro does not work out for you. Email alex@serial-studio.com.

Can I earn a free Pro license?

Yes, on a personal basis. Write a tutorial, donate development hardware, translate docs, share protocol samples or send a pull request. Verified contributions are exchanged for a Pro license valid for 3 to 12 months. See how it works.

Note that academic affiliation alone is not a discount path. Universities and research institutions buy commercial licenses when they need Pro features, official binaries, or support, like any other organization. If the core protocols and standard widgets cover your coursework or research, the GPLv3 source build is free and sufficient.

14 days of Pro, no card required

Serial Studio opens in the free tier, and the trial starts the first time you use a Pro feature. When it ends, the app falls back to the free features instead of locking you out. If you need MQTT, Modbus, CAN, MDF4 or the AI Assistant after that, activate a Pro license.

Download Serial Studio Buy Pro Lifetime, $699