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Minecraft 21w03a

SnapshotLegacy 1.x

Minecraft 21w03a is a Java Edition snapshot released on 20 Jan 2021 under the classic 1.x numbering. Mojang lists Java 8 as the required runtime. It speaks network protocol 1073741835.

Official artwork published by Mojang for Minecraft 21w03a

Minecraft Snapshot 21w03a

Today's Caves & Cliffs snapshot is particularly shiny! You could almost say it's glowing... Oh wait, that's a squid. New Features in 21w03a ​ Added Glow Lichen! Added the Glow Squid!
Image and summary: Mojang Studios, from the official Java Edition patch notes. Not affiliated with Mojang.
Released
20 Jan 2021
Requires Java
Java 8+
Protocol version
1073741835
Data version
2689
Version group
21w
Numbering
Legacy (1.x)
Position
#556 of 920

Official downloads

Served by Mojang. Verify the checksum before running anything.

FileSizeSHA-1Download
Server jar36.6 MBdbe81ef81e20…piston-data.mojang.com ↗
Client jar17.5 MB30d492744e5c…piston-data.mojang.com ↗

The catalogue on 21w03a

Projects that name 21w03a in their own release metadata. Follow any of these to the full filtered list.

Mod loaders

Support declared in each loader's own metadata.

Everything in 21w

25 versions in this group.

Filter list
VersionTypeProtocolReleased
21w44aSnapshot10737418723 Nov 2021
21w43aSnapshot107374187127 Oct 2021
21w42aSnapshot107374187020 Oct 2021
21w41aSnapshot107374186913 Oct 2021
21w40aSnapshot10737418687 Oct 2021
21w39aSnapshot107374186729 Sept 2021
21w38aSnapshot107374186623 Sept 2021
21w37aSnapshot107374186515 Sept 2021
21w20aSnapshot107374185219 May 2021
21w19aSnapshot107374185112 May 2021
21w18aSnapshot10737418505 May 2021
21w17aSnapshot107374184928 Apr 2021
21w16aSnapshot107374184721 Apr 2021
21w15aSnapshot107374184614 Apr 2021
21w14aSnapshot10737418457 Apr 2021
21w13aSnapshot107374184431 Mar 2021
21w11aSnapshot107374184317 Mar 2021
21w10aSnapshot107374184210 Mar 2021
21w08bSnapshot107374184125 Feb 2021
21w08aSnapshot107374184024 Feb 2021
21w07aSnapshot107374183917 Feb 2021
21w06aSnapshot107374183810 Feb 2021
21w05bSnapshot10737418374 Feb 2021
21w05aSnapshot10737418363 Feb 2021
21w03aSnapshot107374183520 Jan 2021

Questions about Minecraft 21w03a

What Java version does Minecraft 21w03a require?

Java 8 is the runtime Mojang's launcher bundles for 21w03a, recorded in the metadata years after release. Versions from this era were built for the Java of their day, so Java 8 is the tested choice rather than a hard floor.

What protocol version does Minecraft 21w03a use?

Minecraft 21w03a speaks protocol 1073741835. A client and a server can only connect when their protocol numbers match.

Where do I download the Minecraft 21w03a 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.

Go deeper

Full compatibility for 21w03aServer software, loaders and the Java requirement in one placeJava 8 downloadsVerified Temurin builds for Windows, macOS and LinuxEverything in 21wSnapshots, pre-releases and candidates in this groupHow 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.

Is this information wrong or missing something? .