Minecraft 1.3.1

ReleaseLegacy 1.x

Minecraft 1.3.1 is a Java Edition full release released on 31 Jul 2012 under the classic 1.x numbering. Mojang lists Java 8 as the required runtime. It speaks network protocol 39.

Released: 31 Jul 2012
Requires Java: Java 8+
Protocol version: 39
Data version: -55
Version group: 1.3
Numbering: Legacy (1.x)
Server software: 2 with builds
Position: #70 of 903

Official downloads

Served by Mojang. Verify the checksum before running anything.

File	Size	SHA-1	Download
Server jar	1.7 MB	`82563ce498bf…`	piston-data.mojang.com ↗
Client jar	4.4 MB	`33167e71e85a…`	piston-data.mojang.com ↗

Versions that can connect to each other

Protocol 39 is shared by these versions, so their clients and servers can talk to each other.

1.3.2

The catalogue on 1.3.1

Projects that name 1.3.1 in their own release metadata. Follow any of these to the full filtered list.

What runs on 1.3.1

Builds are counted from each project's own API; declared support comes from the loader's metadata.

Full compatibility

Software	Latest build	Published	Checksum	Download
Legacy Fabric	#72	28 Jul 2026	Not published	jar ↗
NanoLimbo	#1	13 Nov 2021	Not published	jar ↗
NanoLimbo	1.3.1	Not build based	inferred	loader
Legacy Fabric	0.19.3	Not build based	inferred	loader

Everything in 1.3

3 versions in this group.

Filter list

Version	Type	Protocol	Released
1.3.2	Release	39	15 Aug 2012
1.3.1	Release	39	31 Jul 2012
1.3	Snapshot	Unknown	25 Jul 2012

Questions about Minecraft 1.3.1

What Java version does Minecraft 1.3.1 require?

Minecraft 1.3.1 requires Java 8 or newer. Mojang publishes this in the version metadata, so an older runtime refuses to start it.

What protocol version does Minecraft 1.3.1 use?

Minecraft 1.3.1 speaks protocol 39, which it shares with 1.3.2. Clients and servers on the same protocol can connect to each other.

Where do I download the Minecraft 1.3.1 server jar?

Mojang hosts it directly. This page links to the official file with its SHA-1 checksum and size, so you can verify the download before you run it. We do not mirror or repackage it.

Which server software supports Minecraft 1.3.1?

Legacy Fabric, NanoLimbo publish builds for 1.3.1. Each one is listed with its build number and checksum.

Go deeper

Full compatibility for 1.3.1Server software, loaders and the Java requirement in one place Java 8 downloadsVerified Temurin builds for Windows, macOS and Linux Everything in 1.3Snapshots, pre-releases and candidates in this group How Minecraft version numbers workWhy 1.21 was followed by 26.1, and what happened to 1.22

Metadata from Mojang’s official version manifest. Protocol and data versions from the PrismarineJS minecraft-data project.