gobinsize

A Go program that analyzes Go binaries to determine how much of their size can be attributed to external dependencies.

Installation

go install github.com/imjasonh/gobinsize@latest

Or build from source:

git clone https://github.com/imjasonh/gobinsize.git
cd gobinsize
go build -o gobinsize .

Usage

gobinsize [-verbose] [-svg output.svg] <path-to-binary>

Options

• -verbose: Enable verbose logging for debugging symbol attribution
• -svg <file>: Generate an SVG treemap visualization of dependencies

Example

$ gobinsize ./myapp
Dependency Size Report
======================

github.com/gorilla/mux                               13.62 KB ( 18.8%)
gopkg.in/yaml.v2                                     52.38 KB ( 72.1%)
net                                                   6.59 KB (  9.1%)

Total size: 72.59 KB

SVG Treemap Visualization

Generate a visual treemap to see your dependencies at a glance:

$ gobinsize -svg dependencies.svg ./myapp
Dependency Size Report
======================
...
SVG treemap written to dependencies.svg

The treemap uses colors to distinguish packages and sizes rectangles proportionally to each dependency's contribution to the binary size.

How It Works

gobinsize analyzes Go binaries by:

1. Parsing the binary's debug information (supports ELF, Mach-O, and PE formats)
2. Extracting the Go symbol table and pclntab (program counter line table)
3. Identifying functions and their associated packages/modules
4. Aggregating sizes by top-level module (e.g., github.com/user/repo) or standard library package
5. Calculating the size contribution of each dependency
6. Generating a sorted report showing dependency sizes

Supported Platforms

• Linux (ELF binaries)
• macOS (Mach-O binaries)
• Windows (PE binaries)

Notes

• The binary must be built with Go and contain debug information
• Size measurements are based on function code sizes from the symbol table
• Includes all dependencies: standard library, external packages (github.com, gopkg.in, etc.), and golang.org/x packages
• Dependencies are aggregated by module/top-level package for cleaner output