Weight of Steel
by Cat4blep
Armor weight slows a player's movement based on the total weight of the armor they wear, and Weight of Steel applies that rule in each configured world.
What it does
Weight of Steel calculates the weight of every equipped armor piece and converts the total into a movement speed penalty, applied through the vanilla Slowness effect. The penalty follows the player's real movement speed logic and is capped at a hard maximum, so heavy armor slows a character without stopping it. The armor tooltip shows the weight used in the calculation, and an item tooltip displays each piece's weight.
Each piece's weight comes from its armor stats when no override is set, drawing on values like armor toughness and knockback resistance. A JSON config file sets global tuning and per-item overrides, and a manual override sets a custom value for any item. The mod is published for Fabric, Forge and NeoForge, with builds for 1.20.1, 1.21.1, 1.21.11 and 26.1.2.
Key features
Weight from armor stats
Each piece's weight is derived from its armor toughness and knockback resistance unless a value is set for it.
Movement speed penalty
Total weight converts into a Slowness effect on the player, scaled to the real movement speed and held under a hard cap.
Tooltips
The armor tooltip lists the weight used in the calculation, and the item tooltip shows the weight of each piece.
JSON configuration
A JSON file holds global tuning, per-item overrides and manual custom values for individual armor items.
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Modded armor packs
Armor from other mods can be weighted by its exact item id, so heavier modded sets slow the player like vanilla armor.
Survival and roleplay servers
Server owners can tune the penalty globally, so armor choices carry a movement cost on the whole server.
Who it’s for: Players who want armor to affect movement, and server owners who want to tune how heavy equipment slows the player through a single JSON file.
How it compares
Weight of Steel is a Fabric, Forge and NeoForge mod with the open source MIT License, published for 1.20.1 – 26.1.2 and run by both client and server. ArmorWeight is a Forge-only, open source MIT License mod for 1.20.1 – 1.20.6 and also needs both sides. Weight System is a Forge mod for 1.20.1 under All rights reserved, and Weights covers Forge and NeoForge for 1.19.2 – 1.21.8 with the same environment.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| Weight of Steel | Fabric, Forge and NeoForge | 1.20.1 – 26.1.2 | Client and server | 2026-04-14 |
| ArmorWeight | Forge | 1.20.1 – 1.20.6 | Client and server | 2025-08-24 |
| Weight System | Forge | 1.20.1 | Client and server | 2026-02-26 |
| Weights | Forge and NeoForge | 1.19.2 – 1.21.8 | Client and server | 2026-02-07 |
Questions
Which loaders does Weight of Steel support?
Does the server need Weight of Steel?
Can the weight of modded armor be changed?
More from Cat4blep
What the author says
Weight of Steel is a lightweight armor-weight mod It slows the player based on the actual weight of equipped armor. The mod calculates armor weight from the equipped pieces and converts it into a movement speed penalty. By default it uses armor stats such as armor, toughness, and knockback resistance. If an item has…
Official listing
- Modrinth page
- modrinth.com/mod/weight-of-steel
- Owner
- Cat4blep
- Published
- 2026-04-13
- Updated on Modrinth
- 2026-04-14
- Facts verified
- 2026-10-15