PicoTR

A fast, lightweight traceroute tool written in Go with a rich terminal UI, real-time statistics, ASN lookup, and PNG export.

Features

• Real-time tracing: Continuous ICMP probing with live-updating terminal display.
• Rich TUI: Color-coded RTT bars, packet loss indicators, and dynamic layout adapting to terminal width.
• ASN lookup: Resolves Autonomous System Numbers via Cymru DNS for each hop.
• Route view: Visual AS path map showing how traffic traverses the internet.
• PNG export: Export the current trace table, route map, or all-hops breakdown as a PNG image.
• DNS resolution: Reverse DNS lookups with caching, toggleable on the fly.
• Flexible display: Toggle between simple/detailed mode, units, float precision, color, and more — all without restarting.

Installation

go install github.com/VEX-Systems/picotr/cmd/picotr@latest

Or build from source:

git clone https://github.com/VEX-Systems/picotr
cd picotr
go build -o picotr ./cmd/picotr

Note: Sending raw ICMP packets requires elevated privileges on most systems. Run with sudo on Linux/macOS.

Usage

picotr [options] <target>

Options

Flag	Default	Description
-m	30	Maximum number of hops
-w	3s	Timeout for each probe
-i	1s	Interval between probe rounds
-n	false	Do not resolve hostnames (numeric mode)
-version	—	Print version and exit

Example

picotr google.com
picotr -m 20 -w 2s -n 8.8.8.8

Keybindings

Key	Action
q / Q / Ctrl+C	Quit
d	Toggle DNS / IP display
s	Toggle simple / detailed mode
c	Toggle color
u	Toggle ms units
p	Toggle float precision
x	Show / hide unresponsive hops
a	Toggle ASN display (main view)
r	Enter route view
Backspace	Exit route view
e	Export PNG (trace or route)
t	Export trace table as PNG
a (route view)	Export all-hops PNG

Export

PicoTR can export the current state to PNG files without any external dependencies — the renderer is built in.

Command	Output file
e — trace table	picotr_trace_<target>.png
e (route view) — route map	picotr_<target>.png
a (route view) — all hops	picotr_allhops_<target>.png

Project Structure

cmd/picotr/       # Entry point, CLI flags, keyboard handling
internal/
  probe/          # ICMP prober abstraction (platform-specific implementations)
  trace/          # Tracing engine — concurrent probing, hop statistics
  output/         # Terminal display, ASN lookup, PNG export
  term/           # Terminal raw mode and width detection

Requirements

• Go 1.25+
• golang.org/x/net (ICMP)
• golang.org/x/sys (platform syscalls)

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

License

Distributed under the MIT License. See LICENSE for more information.