ModsFinder

NBTSize

by ErrorNoInternet

NBTSize shows the byte size of the NBT data stored on an item, so players can see how much space an item's data takes.

FabricClient-side onlyGNU Lesser General Public License v3.0 onlyOpen source1.21.11 – 26.3

What it does

Items in Minecraft can carry NBT data, and that data can grow large. NBTSize reports its byte size in two ways, a raw figure for the data before any processing and a packed figure for the size after Minecraft's compression. The mod is released under the GNU Lesser General Public License v3.0 only and is open source. It targets Fabric for game versions 1.21.11 – 26.3 and runs on the client alone, so servers do not need it.

Key features

  1. Raw NBT size

    The raw size shows how large an item's NBT data is without any processing applied to it.

  2. Packed NBT size

    The packed size shows the NBT data's byte count after Minecraft's compression has been applied.

  3. Item size display

    The byte size of the data attached to the inspected item is shown directly on screen.

Compatibility

Latest build for each game version and loader.

26.30.1.2
26.20.1.2
26.1.20.1.2
26.1.10.1.2
26.10.1.2
1.21.110.1.2
ReleaseBetaAlphaNot available

Only full game releases are shown. This mod publishes no snapshot builds.

How it compares

Full comparison

Among the alternatives, NBT Editor is a Fabric mod for 1.17 – 1.21.4 under the MIT License, and the client needs it while the server may skip it. NBT For Give is a client-side only Fabric mod for 1.21 – 26.3 with All rights reserved and is not open source.

ModLoadersGame versionsEnvironmentUpdated
NBTSizeFabric1.21.11 – 26.3Client-side only2026-09-26
NBT EditorFabric1.17 – 1.21.4Client required, server optional2025-06-30
NBT For GiveFabric1.21 – 26.3Client-side only2026-10-04

Questions

Does NBTSize need Fabric API?

The mod is listed for Fabric only. No required dependency is listed for Fabric.

Does the server need NBTSize?

No. Only the player's game needs it, and servers run without it.

Which game versions have files?

Files exist for 1.21.11, 26.1, 26.1.1, 26.1.2, 26.2 and 26.3, with 0.1.2 for 26.3 as the latest Fabric file.

In the catalog

NBTSize is one of 4,058 Storage mods on ModsFinder, and one of 2,474 Storage mods for Fabric. 8,071 mods support Minecraft 26.3.

Storage mods4,058Fabric modsMods for 26.38,071

Similar mods

Mouse Tweaksb1.7.3 – 26.3Inventory Profiles Next1.14.1 – 26.3Clumps1.10.2 – 26.3Shulker Box Tooltip1.16.5 – 26.3Traveler's Backpack1.12.2 – 26.3Tom's Simple Storage Mod1.15.2 – 26.3

What the author says

Display the byte size of an item's NBT data. Packed size displays how large the serialized NBT data is after Minecraft's compression. Raw size displays how large the NBT data is without any processing.
ErrorNoInternet, on the Modrinth page

Official listing

Owner
ErrorNoInternet
Published
2026-04-13
Updated on Modrinth
2026-09-26
Facts verified
2026-10-15

Tags

StorageUtility
Open on ModrinthCompare