zstdnet-minekuai
by xuenai
zstdnet-minekuai is a transparent proxy that compresses traffic between a Minecraft client and server, and it installs on both sides of the connection.
What it does
The proxy relays client and server traffic and applies ZSTD compression to it, which cuts public bandwidth by up to 95% on repetitive data. Coverage includes dedicated servers, LAN-hosted servers, plugin builds, host setups and singleplayer worlds opened to LAN. A built-in live HUD shows whether ZSTD is active during play, along with the cumulative traffic compression ratio and connection count.
Vanilla status pings pass through unchanged, so server lists still show the player count and MOTD. Installs on the client and on the server are both needed to run the compression, and a client without the mod still connects normally. The mod is published for Fabric, Forge and NeoForge across 27 release versions, 1.16.5 – 26.3, and it requires that ZstdNet verify genuine accounts itself during login, so the access token never leaves the client. The code is not open source; it is released under All rights reserved.
Key features
Live compression HUD
An in-game display shows whether ZSTD is active and the current rate, so players can check the connection without a command.
Chunk Reference Cache
A chunk the server has already sent in the same session is replaced by an 8-byte reference token, and the client replays its cached bytes.
Cross-session warm references
Fully sent chunks persist to disk, so after a reconnect a 16-byte token can stand in for a chunk the client still holds.
Byte-level patching
A slightly changed chunk is sent as a delta against the baseline the client already holds, rather than as a whole block.
Long-distance matching
On servers where the same large structure recurs within minutes, long-distance matching squeezes the ratio further.
Compatibility
Latest build for each game version and loader.
26.x5 of 5 versions with builds
1.21.x11 of 11 versions with builds
1.20.x6 of 6 versions with builds
1.19.x3 of 3 versions with builds
1.18.x1 of 1 version with builds
1.16.x1 of 1 version with builds
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Large modpack servers
Create-heavy modpack servers resend the same chunks when players walk out and back or cross dimensions, which the reference cache is built to catch.
Who it’s for: Server owners running large modpacks, and players on dedicated, LAN or plugin-based servers who want lower public-network usage without changing how they connect.
Questions
Does zstdnet-minekuai have to be installed on both sides?
Which loaders does zstdnet-minekuai support?
Does the mod change how a connection to the server is made?
What the author says
🗜️ Compresses multiplayer bandwidth down to ~5–20%, cutting public-network usage by 80%+. With auto-takeover on, players keep typing the same IP and port — nothing new to learn. Vanilla players with no mod installed still connect normally and are unaffected. CRC and ZSTD are multiplicative, not either/or: CRC…
Official listing
- Modrinth page
- modrinth.com/mod/zstdnet-minekuai
- Owner
- xuenai
- Published
- 2026-06-21
- Updated on Modrinth
- 2026-09-26
- Facts verified
- 2026-10-15