bl4 Community Tools

Save editing, serial decoding, and research tools for Borderlands 4. Built by the community, for the community.

Read the Docs View on GitHub

What You Can Do

Save Editing

Decrypt, edit, and re-encrypt your BL4 save files with ease

Serial Decoding

Decode item serials to reveal weapon parts, stats, and more

Items Database

Track and verify item data from community contributions

Learn BL4 Internals

A guide to reverse engineering Borderlands 4 game data

Quick Start

Download the CLI for your platform and start editing:

Windows macOSApple Silicon macOSIntel Linuxx86_64 LinuxARM64

Usage

# Decrypt a save file
bl4 decrypt -i 1.sav -o character.yaml

# Decode an item serial
bl4 decode '@Ugr$ZCm/&tH!t{KgK/Shxu>k'

# Edit a save in your $EDITOR
bl4 edit -i 1.sav

Help the Community

Every contribution helps build better tools for everyone. Here are some ways to get involved:

Share Your Data

Sync your items to the community database with bl4 idb push to help build accurate part mappings.

Submit Save Files

Can't run the tools? Share your .sav files and Steam ID via GitHub Issues or email.

Contribute Code

PRs welcome for bug fixes, new features, documentation, and research discoveries.