
Modrinth · Minecraft mod
Effortless Building
Makes building easier by providing tools like mirrors, arrays, build modes and a block randomizer. For survival and creative mode.
Quick answer
Which Effortless Building release matches 1.21.11 Fabric?
Effortless Building 4.3 targets 1.21.11 with Fabric, NeoForge. Installation on the client is optional. Installation on the dedicated server is optional. No extra mods listed for this file.
Where it goes
Is Effortless Building required on the client, server, or both?
Installation on the client is optional. Installation on the dedicated server is optional.
The source marks this as usable on both the client and server.
What else does Effortless Building 4.3 need?
4.3 on 1.21.11 Fabric. Every mod below is checked against that same setup.
This file does not list any required mods. Do not add a library just because a different file uses it.
This file does not list any required or optional mods.
Before you install it
Add Effortless Building without breaking your instance.
Built for Effortless Building 4.3 on 1.21.11 Fabric. Pick another file and the loader, install side or required mods may change.
- 01
Stick to this file
Use 4.3. It targets 1.21.11 with Fabric, NeoForge; another release may have different loader, side or dependency requirements.
- 02
Bring the mods it needs
This file does not list any required mods. Do not add a library just because a different file uses it.
- 03
Put it on the correct side
Installation on the client is optional. Installation on the dedicated server is optional.
- 04
Pick the file you checked
Use the “Get this file” button beside 4.3. It opens that exact file at the source.
About this project
What does Effortless Building add?
Many mods make it easier to break blocks, but not many focus on placing them. Even the most experienced players still often place blocks one by one. This mod makes building easier by providing tools like mirrors, arrays, build modes and a block randomizer.
- Place and break multiple blocks at once
- Mirror blocks in realtime
- Place random blocks using the Randomizer Bag
- Undo and redo
- Fully supported in survival mode
Build Modes
Hold ALT to open the radial menu and select a build mode. With a block in hand, right-click to pick the starting position. Aim somewhere else, then right-click again to build the shape.
Build modes can be used to place blocks, break blocks, and interact with certain blocks. When holding a tool, right-clicking will interact with all the blocks in the shape. For example, stripping logs with an axe, pathing with a shovel, tilling with a hoe, and placing liquids with a bucket.
Available build modes:
- Disabled
- Single
- Line
- Wall
- Floor
- Cube
- Diagonal Line
- Diagonal Wall
- Slope Floor
- Circle
- Cylinder
- Sphere
On the right side of the radial menu you can find additional options for each build mode. On the left side you can find buttons for undo/redo, replace options, opening the modifier settings and config screens.
More videos
Build Modifiers
Modifiers can place additional blocks for each block you placed. You can enable any number of modifiers in the modifier settings. Open the modifier settings with the button in the radial menu, or use the keybind (default NUMPAD+).
- Mirror. Place a mirror at a position of a certain size. Each block placed on one side gets mirrored to the other side.
- Array. Copies the block you placed in a certain direction a certain number of times. Useful for repeated builds like tunnels and walls.
- Radial Mirror. Divides an area in slices around a central point. Each slice copies your block placements.

Randomizer Tool
This item allows you to place random blocks. Configure the tool by shift-rightclicking when in hand.
- Use it in combination with build modes and build modifiers.
- While placing a shape, you can open the randomizer tool and change its settings. You can preview those settings in realtime!
- Setting the ratio of an empty slot will cause air gaps to appear in your shape.

Crafting recipe: 3 iron ingots, 1 redstone dust, 1 any flower.
Replace Options
Use the button to the left of the radial menu to cycle through replace options.
- Replace Only Air: You can only place blocks where there was air. Replaceables such as short grass and ferns can still be replaced.
- Replace Blocks And Air: You can replace blocks and air.
- Replace Only Blocks: You can only replace blocks, not air.
- Filter By Offhand: You can only replace blocks that match the block in your offhand.
Undo and Redo
Press CTRL+Z to undo and CTRL+Y to redo placing blocks.
Survival-friendly
Playing this mod in survival mode is fully supported. All actions consume the right number of blocks from your inventory. It is fully configurable, so you can find settings that feel balanced for you.
Here's a small sample of what you can configure:
- How far away you can place blocks
- The maximum number of blocks placed at once
- The maximum size of the mirror and array
- Whether you can break and replace multiple blocks at once, including if tools are required, if they should use durability, etc. By default, you can break and replace blocks that you placed in the same play session.
The functional settings can be found in the radial menu. On a server, you can only edit functional settings if you are an admin.

FAQ
"Can I add this mod to my modpack?"
Yes, certainly!
"Is this mod available for bedrock edition?"
Yes, ExterLeo made a version that works in Bedrock Edition.
"Is this a client-side only mod?"
No, it needs to be installed on both server and client. The server part places the blocks in bulk. If there was no server part, the client would need to send all the blocks individually, which will overload most servers.
"Am I allowed to make my own version of this mod?"
Yes, as long as you comply with the LGPL-3.0 license (usually this means: link to this page, license your modification under LGPL-3.0, make the code visible and state significant changes).
Mod Spotlights
Mod Spotlights
Credits
Many thanks to Grimmauld for porting to 1.16, Dashos for fixing 'fake player' related crashes and manapart for porting to 1.19!
Radial Menu inspired by Chisels & Bits by AlgorithmX2
Project description from Modrinth.
Pick your setup
Effortless Building by Minecraft version and loader
Choose the version and loader you play, then open the matching release.
26.1.2
2 loader builds1.21.11
2 loader builds1.21.5
2 loader builds1.21.1
2 loader builds1.20.1
2 loader builds1.19.4
2 loader builds1.19.2
2 loader buildsCheck the dependencies, then try the file in a copied instance before changing a world you care about.
Recent files
Effortless Building versions and loaders
4.3
effortlessbuilding-4.3+1.21.11.jar
1 Aug 2026
4.2
effortlessbuilding-4.2+1.21.11.jar
31 Jul 2026
4.1
effortlessbuilding-4.1+1.21.11.jar
8 May 2026
4.0
effortlessbuilding-4.0+1.21.11.jar
4 May 2026
Looking for an older file? The official Modrinth project page is in Resources.