Also on curseforge

Forge mod.

Uninstalling older versions of this mod and using it on a world that previously had it installed may have negative consequences!

Bigger stacks

Allows you to increase stack size beyond 64, up to ~1 billion (though I don't recommend you go that high).

Control the stack size of individual items

The mod allows you to change the stack size of items based on tags, what mod it comes from, and more using rules.

Quickstart

When you load into a world with the mod unconfigured, it will show you this prompt:

<img src="https://media.forgecdn.net/attachments/589/800/prompt.PNG" width="594" height="168" />

Clicking on the command or running it will open a configuration GUI.

You can open this GUI at any time by running /biggerstacks quicksetup

Compatibility

With a mod like this, it is very likely that some things will be incompatible. If you find any issues, or things not working as expected, report them on codeberg.

Some item transport mod (xnet, modular routers, pretty pipes, cyclic) have been changed for bigger stacks. There is some more information about the changes in the config file.

Please report any issues/incompatibilities you find with this mod to me, not the author of the other mod.

1.12?

There are very similar mods for 1.12 already available