CANExplorer

CANBus monitoring for the modern man!

Monitor, analyse, diagnose, simulate and test CAN, CAN FD and LIN buses — on Linux, Windows and macOS, with any adapter python-can supports, or without hardware on a virtual bus.

Documentation · Quick start · Downloads · Changelog

Features

Monitoring and analysis

• Live view of any python-can interface: SocketCAN, PCAN, Vector, Kvaser, gs_usb, slcan and other serial adapters, virtual buses; CAN FD with a separate data bitrate; channel detection
• Dashboard with frame rates, bus load, error frames, bus activity, traffic breakdown and the busiest identifiers
• Trace and per-identifier overview (cycle times, changed bytes highlighted, sortable columns), display filters such as 100-1FF !123 ext rx fd, search by text, data pattern or signal condition, and bookmarks
• Millions of frames per session: older frames are paged to disk
• Bus health: error state timeline, error frames, TEC/REC and bus load over up to an hour
• Remote buses: can-server shares the interfaces of e.g. a Raspberry Pi in a vehicle over the network
• MQTT: publish decoded signals (and frames) to a broker for dashboards and home automation, from the application or can-server, and optionally send frames requested over MQTT
• MCP: can-mcp exposes a bus to an AI agent over the Model Context Protocol — inspect identifiers, decode frames and protocols, run the reverse-engineering analysis, correlate fields, promote results to a DBC, read trouble codes over OBD-II/UDS, and optionally transmit; as tools, resources and prompts, behind permission tiers
• Signal plots with zoom and pan over the whole buffer, two cursors with values and statistics, several signals per chart and CSV export
• Reverse engineering: bit and byte statistics per identifier and a notch; automatic detection of checksums, counters, multiplexers and values; matching fields to database signals, CSV/GPS logs or polled OBD-II values; grouping fields that carry the same signal across messages; event markers; frame-interval (Δt) and per-byte timing graphs; and bit fields to plot without a database or add to one

Recording and replay

• ASC, BLF, CSV, candump LOG, PEAK TRC, SQLite, ASAM MF4 and gzip compressed text logs
• Splitting into numbered files by size or time, and triggered recording with conditions such as EngineData.EngineSpeed > 6000, keeping the time before and after the event
• Replay at 0.25× to 10× or as fast as possible, with pause and jumping to any position
• Replay of a recording onto a real bus, filtered and repeated
• Several buses on one timeline, and simulated gateways forwarding frames between them
• Comparison of two recordings: identifiers only in one of them, changed cycle times and payloads, and signal values, aligned by time, by a trigger identifier or by frame sequence

Signal databases

• Vector DBC, BUSMASTER DBF, AUTOSAR ARXML (including container PDUs), Kayak KCD, PCAN SYM and LIN LDF
• Database editor for CAN and LIN databases (frames, signals, nodes, encodings, schedule tables) with a bit layout view and consistency checks, and conversion between the formats

Diagnostics and protocols

• UDS over ISO-TP and the LIN transport layer: sessions, reset, data identifiers, security access with your own seed/key algorithm, DTCs, routines; CANdelaStudio CDD and ASAM ODX/PDX descriptions for named and decoded identifiers
• OBD-II (SAE J1979): a dedicated page for the standard emissions diagnostics — scan for supported values, watch them live, read and clear trouble codes, and read the VIN
• ECU flashing over UDS (RequestDownload/TransferData) from Intel HEX, S-record or binary files, with progress
• DoIP (Diagnostics over IP, ISO 13400-2): finds DoIP entities, connects with routing activation (optionally over TLS) and runs diagnostics and flashing over Ethernet; a simulated entity works without a vehicle
• SOME/IP over automotive Ethernet: listens on UDP, discovers the services offered through SOME/IP-SD and shows the decoded messages; load a FIBEX file to deserialize the payloads into named signals
• Automotive Ethernet capture: open a pcap file (or capture live on Linux) and decode the stack (Ethernet, VLAN, IPv4/IPv6, UDP/TCP) and the protocols on top — SOME/IP, DoIP, gPTP and AVTP
• UDS discovery: scan an ECU for the services, data identifiers, subfunctions and routines it exposes, classifying the answers, for reverse engineering diagnostics; and fuzz it with mutated requests, detecting hangs and crashes
• Bus gateway: forward frames between two connections with filtering, identifier rewriting and rate limiting
• XCP/CCP measurement and calibration: read measurements live and read/write calibration values by address or by name from an A2L file, with simulated slaves for trying it without hardware
• GMLAN (GMW3110) diagnostics for GM/Opel vehicles — data identifiers, modes, security access and trouble codes — over CAN, including single-wire (SWCAN, 33.3 kbit/s) buses; a simulated ECU works without hardware
• GM Class 2 (SAE J1850 VPW) for the pre-CAN GM vehicles of 1996–2007 (e.g. the 99–06 P01/P59 PCMs): monitor the 10.4 kbit/s single-wire bus and run SAE J1979 diagnostics (PIDs, VIN, trouble codes) through an ELM327/OBDLink adapter; a simulated ECU works without hardware
• J1939: nodes with their address claims, DM1/DM2 trouble codes and lamps, clearing codes, requests and sending parameter groups by name with BAM or RTS/CTS
• CANopen master: NMT, SDO access to object dictionaries from EDS/DCF files, PDO mappings with live values, emergency messages
• CANopen over EtherCAT (CoE): EtherCAT slaves with their states, object dictionaries (SDO information or EDS), PDO assignment and emergencies; real adapters need the ethercat extra, a simulated network works without
• Physical I/O: switch the digital outputs of a USB I/O adapter (aio_usb) and watch its inputs and analogue values, from the tool or test scripts; needs the io extra, a simulated device works without
• Decoding of ISO-TP, UDS, J1939, NMEA 2000 (marine, with Fast Packet), CANopen, LIN and J1587 frames in the trace
• LIN master schedule tables

Simulation and test automation

• Simulated ECUs written in Python, controlled from QML panels
• ECU test scripts with checks, timing measurements and UDS requests; pass/fail verdicts in the Tests view or headless with can-test, with HTML, JUnit and Markdown reports for CI; parametrised test cases and requirement traceability

Workspace

• Connections, databases, filters, plots and scripts saved in one workspace file
• Dashboard-style interface with six colour themes, a command palette (Ctrl+K) and English, German, French, Chinese and Japanese texts

See the documentation for a guide to every feature.

Installation

Installers

Download the installer for your platform from the releases: a setup.exe for Windows, an AppImage or .deb for Linux and a .dmg for macOS (Apple silicon). Portable zip archives are attached as well. No Python installation is needed.

On Linux, CANExplorer is also a snap: sudo snap install canexplorer, then connect the hardware interfaces with sudo snap connect canexplorer:can-bus (SocketCAN) and sudo snap connect canexplorer:raw-usb (USB adapters).

From source

With uv and Python 3.10 or newer:

git clone https://github.com/AKJ7/CANExplorer.git
cd CANExplorer
uv sync                  # Add --extra mf4 for ASAM MF4 log files (installs asammdf, numpy and pandas),
                         # --extra ethercat for EtherCAT adapters (installs pysoem),
                         # --extra io for USB I/O adapters (installs pyusb and libusb)
uv run canexplorer

On Linux, uv run canexplorer --install-desktop-entry adds CANExplorer with its icon to the application menu.

Interfaces

CANExplorer supports every interface of python-can 4.6. Install the vendor's driver for your adapter; the supported interfaces page lists the drivers, CAN FD support and the Linux kernel drivers.

Interface	Hardware	Platforms
SocketCAN (socketcan)	Any adapter with a Linux kernel driver: PEAK, Kvaser, candleLight/gs_usb (CANable), ETAS ES58x, 8devices, EMS, esd, MCP2515/MCP251xFD (Raspberry Pi hats), virtual vcan; LIN through sllin	Linux
PEAK PCAN (pcan)	PCAN-USB, PCAN-USB FD, PCAN-PCI(e), PCAN-LAN	Windows, Linux, macOS
Vector (vector)	VN16xx, VN56xx and other XL Driver Library devices, Vector virtual channels	Windows
Kvaser (kvaser)	Leaf, U100, Memorator, USBcan	Windows, Linux
IXXAT (ixxat)	HMS IXXAT USB-to-CAN, CAN-IB	Windows
ETAS (etas)	ES581, ES582, ES584, ES891 (BOA)	Windows
Intrepid neoVI (neovi) ¹	neoVI, ValueCAN, RAD-Galaxy	Windows, Linux, macOS
NI-XNET (nixnet) ¹	National Instruments NI-XNET devices	Windows
NI-CAN (nican)	National Instruments NI-CAN devices	Windows
SYS TEC (systec)	USB-CANmodul	Windows
8devices USB2CAN (usb2can)	USB2CAN (Korlan)	Windows
Thorsis isCAN (iscan)	isCAN	Windows
Neousys (neousys)	CAN ports of Neousys industrial computers	Windows, Linux
CANalyst-II (canalystii) ¹	Chuangxin CANalyst-II	Windows, Linux, macOS
CANtact (cantact) ¹	CANtact, CANable	Windows, Linux, macOS
gs_usb (gs_usb) ¹	candleLight/gs_usb firmware adapters through libusb	Windows, Linux, macOS
slcan (slcan)	Lawicel CANUSB, CANable (slcan firmware), USBtin and other serial slcan adapters	Windows, Linux, macOS
GVRET (gvret)	ESP32RET boards, Macchina M2 (M2RET), CANDue: SavvyCAN's GVRET protocol over USB serial or WiFi	Windows, Linux, macOS
J2534 (j2534)	J2534 pass-thru devices: Mongoose, CarDAQ, OpenPort 2.0, Bosch, Autel …; 32-bit drivers through a bridge process	Windows
ELM327 / OBDLink (elm327)	OBDLink MX+, LX, SX, EX and ELM327 compatible OBD adapters over USB, Bluetooth or WiFi, for diagnostics	Windows, Linux, macOS
J1850 VPW / GM Class 2 (elm327_vpw)	GM "Class 2" 10.4 kbit/s single-wire bus of 1996–2007 GM vehicles, through an ELM327/OBDLink adapter (not CAN)	Windows, Linux, macOS
python-can serial (serial)	Adapters with python-can's serial protocol	Windows, Linux, macOS
Robotell (robotell)	Robotell USB-CAN	Windows, Linux, macOS
Seeed Studio (seeedstudio)	USB-CAN Analyzer	Windows, Linux, macOS
socketcand (socketcand)	SocketCAN buses of another Linux computer, over the network	Windows, Linux, macOS
CANExplorer remote (canexplorer_remote)	Buses shared by can-server on another computer, e.g. a Raspberry Pi	Windows, Linux, macOS
UDP multicast (udp_multicast) ¹	A software bus between computers over UDP multicast	Windows, Linux, macOS
Virtual (virtual)	A software bus inside CANExplorer, no hardware needed	Windows, Linux, macOS

¹ Needs Python packages that the installers do not include: run from source with uv sync --extra drivers.

Try it without hardware

Run the example ECU tests against the example engine simulation on a virtual bus:

uv run can-test examples/testing/vehicle_tests.py \
    --database examples/simulation/vehicle.dbc \
    --simulation examples/simulation/engine_simulation.py \
    --report report.html

In the application, connect to a VirtualBus, load examples/simulation/vehicle.dbc and run engine_simulation.py in the Simulation view; the quick start walks through it.

Command line

Command	Purpose
uv run canexplorer	The application. Options such as --log_level DEBUG, or CANEXPLORER_* environment variables
uv run can-test SCRIPT …	Run ECU test scripts on a bus; exit code and HTML/JUnit reports for CI
uv run can-db-convert IN OUT	Convert signal databases, e.g. vehicle.dbc vehicle.dbf, or one bus with system.arxml powertrain.dbc --bus Powertrain

Development

uv run pytest                                  # Tests (headless Qt, python-can virtual buses)
uv run ruff check . && uv run black --check .  # Lint and formatting
uv run --group docs mkdocs serve               # Documentation preview on http://127.0.0.1:8000
uv run python packaging/build.py --archive     # Standalone bundle in dist/ (--backend nuitka to compile)
uv run python packaging/installer.py           # Installers of the platform in dist/installers

The core (can_explorer/core) is Qt-independent asyncio code; can_explorer/gui adapts it to the QML interface in can_explorer/gui/qt, and Qt and asyncio share one event loop through qasync. The development guide covers the architecture, testing, packaging and contributing.

License

MIT, as declared in pyproject.toml.