Paradox Checksum Patcher

A tool that patches Paradox game executables to bypass ironman checksum validation, allowing you to use mods that change checksum while still earning achievements.

Note: This patcher does NOT enable console commands or achievement-disabling game rules in ironman mode.

Important

The patcher only modifies the current game executable. If Paradox releases a game update, you'll need to run the patcher again.

Installation

Option 1: Download Pre-built Binary

Download the latest paradox-checksum-patcher.exe from Releases

Option 2: Build from Source

Prerequisites: Install Rust from rust-lang.org

# Clone the repository
git clone https://github.com/DaniPopes/paradox-checksum-patcher.git
cd paradox-checksum-patcher

# Build release binary
cargo build --release

# Binary will be at: target/release/paradox-checksum-patcher[.exe]

Usage

Option 1: Place in Game Directory

1. Place paradox-checksum-patcher.exe in your game directory (Steam: Right-click game → Manage → Browse local files)
2. Run paradox-checksum-patcher.exe

The patcher will automatically detect and patch supported game executables in the directory.

Option 2: Run from Command Line

# Auto-detect games in current directory
./paradox-checksum-patcher.exe

# Patch specific file
./paradox-checksum-patcher.exe path/to/eu4.exe

# Patch multiple files or directories
./paradox-checksum-patcher.exe ./eu4.exe ~/.local/share/Steam/steamapps/common/Europa\ Universalis\ V/binaries/

Supported Games and Platforms

	Windows	Linux	macOS
Europa Universalis IV	✓	✗	✗
Europa Universalis V	✓	✗	✗
Hearts of Iron IV	✓	✗	✗

Note: The table above refers to native game executables. (Note that EU5 doesn't have native Linux/macOS binaries) However, the patcher itself is cross-platform and can patch Windows executables from Linux/macOS, making it usable with Proton.