Tester Mod
by Komorebi_awa
Tester Mod lets developers and players spawn configurable tester entities that report the damage they receive in real time, and it is open source under the MIT License.
What it does
Tester entities are placed by the player with a Tester Setter item, and each one records the damage it takes. Its damage output is shown as system messages, so chat stays clear. The entries separate raw damage from damage after armor and resistance, and from damage after invulnerability, and they also name the damage type and the game tick at which it landed.
The tester can be configured through a GUI opened by right-clicking it with the Tester Setter. Options include armor value, toughness, maximum health and knockback, along with a toggle for whether zero-damage entries appear. Shift with right-click adjusts invincibility and the zero-damage display for the player's own tester settings. Several testers can run at once, each showing a name prefix so its output can be told apart. Testers with the Fire Resistance effect ignore fire-type damage.
The mod runs on Forge and NeoForge for 1.20.1 and 1.21.1. Only the client needs it while the server does too, so both sides must run it. The source code is public, and the project is open source under the MIT License.
Key features
Spawned tester entities
Stationary tester entities can be spawned to take hits and report how much damage they absorbed.
Detailed damage breakdown
Each report lists raw damage, post-armor and resistance damage, and post-invulnerability damage, with the damage type.
Player tester mode
Players take on the tester role by right-clicking empty air with the Tester Setter, so their own damage intake can be read.
Full tester configuration
Armor, toughness, maximum health, knockback and zero-damage display can be set from a GUI.
Fire resistance handling
Testers with the Fire Resistance effect ignore fire-type damage, which keeps fire tests separate from other damage.
Gallery
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Who it’s for: Mod developers who need to measure damage values, and players who want to see how damage mechanics behave in their own world.
How it compares
Spawn Egg Information is a client-side only mod under the MIT License, published for Fabric, Forge and NeoForge across 1.18.2 – 1.21.1, and it is not open source. Damage Numbers is also client-side only, under All rights reserved and not open source, for 1.19.4 – 1.21.1 on the same three loaders. Dimension Follow is server required with client optional, open source under the MIT License, and covers 1.20.1 – 26.2.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| Tester Mod | Forge and NeoForge | 1.20.1 – 1.21.1 | Client and server | 2026-08-25 |
| Spawn Egg Information | Fabric, Forge and NeoForge | 1.18.2 – 1.21.1 | Client-side only | 2025-05-19 |
| Dimension Follow | Fabric, Forge and NeoForge | 1.20.1 – 26.2 | Server required, client optional | 2026-08-04 |
| Damage Numbers | Fabric, Forge and NeoForge | 1.19.4 – 1.21.1 | Client-side only | 2024-06-26 |
Questions
Which loaders does Tester Mod support?
Does the server need Tester Mod?
How are tester entities placed?
In the catalog
Tester Mod is one of 36,990 Utility mods on ModsFinder, and one of 14,575 Utility mods for Forge. 32,366 mods support Minecraft 1.21.1.
Similar mods
What the author says
Tester Mod provides configurable damage testing entities for Minecraft NeoForge 1.21.1, perfect for mod developers and players who want to analyze damage mechanics.
Official listing
- Modrinth page
- modrinth.com/mod/tester-mod
- Owner
- Komorebi_awa
- Published
- 2026-07-28
- Updated on Modrinth
- 2026-08-25
- Facts verified
- 2026-10-15