PacketDebug
by Fadeorite1
PacketDebug is a Fabric utility that shows live network traffic inside the game, opened with the F6 key.
What it does
Pressing F6 opens a real-time panel that tallies how much data moved over the connection in the most recent half minute. Packets are ranked by throughput in KiB/s, which makes it possible to see which packet types take up the most bandwidth. Separate views cover server-to-client (S2C) and client-to-server (C2S) traffic, so the direction of each flow is clear.
The tool suits people who want to track down high-traffic problems, compare the effect of changing mod configurations, or simply look at how Minecraft's network layer behaves. It is a debugging aid and does not change how the game plays. Players add it to their own game, and a server needs no copy. The mod is published for Fabric and the single game version 1.21.6, and the code is under the MIT License, but the project is not open source.
Key features
Live traffic panel
The F6 panel shows packet statistics for the most recent 30 seconds and updates while the game runs.
Bandwidth sorting
Packet types are ranked by KiB/s, so the heaviest senders appear at the top of the list.
Direction views
Separate S2C and C2S views show traffic from the server and traffic from the client on their own.
Gallery
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Finding heavy packets
A player who sees lag on a busy server can open the panel and check which packet type uses the most bandwidth.
Checking mod settings
Someone tuning mod configurations can watch the traffic figures change after each adjustment.
Who it’s for: Players who are curious about the network side of the game, and anyone diagnosing high traffic on a multiplayer server or a modded client.
Questions
Does PacketDebug need to be installed on the server?
Which loader does PacketDebug support?
Can PacketDebug show traffic from the last hour?
In the catalog
PacketDebug is one of 36,990 Utility mods on ModsFinder, and one of 25,772 Utility mods for Fabric. 13,625 mods support Minecraft 1.21.6.
Similar mods
What the author says
PacketDebug — A lightweight in-game network traffic analyzer for Minecraft. Press F6 to open a real-time GUI showing packet traffic statistics for the last 30 seconds. Packets are sorted by KiB/s and separated into S2C (Server → Client) and C2S (Client → Server) views, making it easy to identify which packet types…
Official listing
- Modrinth page
- modrinth.com/mod/packetdebug
- Owner
- Fadeorite1
- Published
- 2026-03-23
- Updated on Modrinth
- 2026-03-23
- Facts verified
- 2026-10-15