pdfcpu: a PDF processor written in Go with CLI and API support

May 11, 2026 · View on GitHub

pdfcpu is a PDF processing library written in Go.

It is compatible with all PDF versions. Support for PDF 2.0 (ISO-32000-2) is evolving and continuously improving.

Installation

CLI

👉 CLI Installation instructions

Go API

👉 API Installation instructions

Usage

CLI

Validate against PDF 2.0 (ISO-32000-2):

pdfcpu validate input.pdf

Merge two PDFs:

pdfcpu merge out.pdf in1.pdf in2.pdf

Go API

See API documentation for usage examples.

Features

Validate, optimize, split, trim, and merge PDFs
Extract and manipulate images, fonts, and metadata
Encrypt and decrypt PDFs
Resize and rotate pages
Add and remove stamps and watermarks
Manage digital signatures (ongoing work)
Manage attachments and more...

In Action

Common operations and examples:

Command Set

Complete list of supported commands:


annotations	attachments	booklet
bookmarks	boxes	certificates
change owner password	change user password	collect
config	create	crop
cut	decrypt	encrypt
extract	fonts	form
grid	images	import
info	keywords	merge
ndown	nup	optimize
pagelayout	pagemode	pages
permissions	portfolio	poster
properties	resize	rotate
signatures	split	stamp
trim	validate	viewerpref
watermark	zoom

Motivation

pdfcpu aims to provide comprehensive PDF processing capabilities implemented in Go.

It focuses on correctness, robustness and independence from external dependencies.

Focus

comprehensive PDF processing functionality
minimal external dependencies
predictable and stable behavior

Documentation

Project documentation: https://pdfcpu.io

CLI

Command help: pdfcpu [command] --help

Go API

Package documentation: https://pkg.go.dev/github.com/pdfcpu/pdfcpu
API documentation: https://pkg.go.dev/github.com/pdfcpu/pdfcpu/pkg/api
Examples:
- https://github.com/pdfcpu/pdfcpu/tree/master/pkg/api/test
- https://github.com/pdfcpu/pdfcpu/tree/master/pkg/samples

Contributing

Contributions are welcome.

Report bugs or propose changes via issues
Discuss ideas on the discussion board
For PRs, please open an issue or discussion first v

Guidelines

Base your work on the latest commit
Include verbose output (pdfcpu cmd -vv ...) and a sample PDF when reporting issues
Please sign your commits

Reporting crashes

Crashes may occur due to the wide variety of PDF producers and formats in use, including older or non-compliant files. In many cases this is related to validation issues or edge cases in the parser.

Even with relaxed validation, some files cannot be processed. These cases are essential for improving pdfcpu by extending validation and handling additional real-world PDFs.

If you encounter a crash, please report it.

Start by validating the file using the CLI:

pdfcpu validate -vv <file.pdf>

Include in your report:

the command used
verbose output (-vv)
a sanitized sample PDF

If validation crashes for a PDF that opens in Adobe Reader or macOS Preview, it is likely we can extend relaxed validation and provide a fix.

If the file cannot be opened by both Adobe Reader and macOS Preview, we cannot support it.

Please include a sample PDF to reproduce the issue whenever possible.

Contributors

Thanks 💚 to all contributors:


_{Horst Rutter}	_haldyr	_Vyacheslav	_{Erik Unger}	_{Richard Wilkes}	_minenok-tutu	_{Mateusz Burniak}
_{Dmitry Harnitski}	_ryarnyah	_{Sam Giffney}	_{Carlos Eduardo Witte}	_minusworld	_{Witold Konior}	_joonas.fi
_{Henrik Reinstädtler}	_VMorozov-wh	_{Benoit KUGLER}	_{Adam Greenhall}	_moritamori	_JanBaryla	_{TheDiscordian}
_{Rafael Garcia Argente}	_truyet	_{Christian Nicola}	_{Benjamin Krill}	_{Peter Wyatt}	_{Kroum Tzanev}	_{Stefan Huber}
_{Juan Iscar}	_{Eng Zer Jun}	_{Dmitry Ivanov}	_{Rene Kaufmann}	_{Christian Heusel}	_Chris	_{Lukasz Czaplinski}
_{Joel Silva Schutz}	_semvis123	_guangwu	_{Yoshiki Nakagawa}	_{Steve van Loben Sels}	_Yaofu	_vsenko
_{Alexis Hildebrandt}	_{Sivukhin Nikita}	_{Joachim Bauch}	_kalimit	_{Andreas Erhard}	_{Matsumoto Toshi}	_{Carl Wilson}
_LNAhri	_vishal	_{Andreas Deininger}	_{Robert Raines}	_{Frank Anderson}	_{Sven Lilienthal}	_{Florian Kinder}
_mdmcconnell	_{Bradley Erickson}	_doronbehar	_joeyave	_{Zhenbang Wei}