Minecraft 25w10a Update - What's New
Added test block for map makers and technical improvements. Test blocks can run game tests and validate contraptions.
Overview
Minecraft 25w10a is a weekly development snapshot for Minecraft: Java Edition, published on March 5, 2025. Snapshots are Mojang's weekly previews of in-progress features (development week 10 of 2025), shipped early so the community can test and report problems before anything is finalized. This one logs 5 changes you can try in a throwaway test world.
The work in this update spans blocks & items and commands. On the blocks & items side it brings test block and Test block can run game tests for map validation.
This build is part of the development cycle leading to a future 1.21.x / 1.22 release. Treat it as a preview rather than a destination: features can change, be renamed, or be cut entirely before they reach the stable release, so it is meant for testing and feedback, not for your main world or a live server.
Changes
#Blocks & Items(3)
- Added test block (operator/creative only)
- Test block can run game tests for map validation
- Useful for data pack and map development
#Commands(2)
- Improvements to test framework
- Better error reporting for data packs
Server Admin Migration Guide
- Snapshot only - do not use in production
Known Issues
- Test block is operator-only and not accessible in survival
What This Means
For players
Snapshots are opt-in through the official launcher. Always make a copy of any world before opening it in 25w10a, because development builds can corrupt saves and there is no guarantee the world will open in a later version. Use a fresh test world to try the new content safely.
For server admins
Do not run 25w10a on a public server. Snapshots are unsupported by server software and most plugins. Spin up a private staging instance, confirm your plugins load, and report regressions while there is still time to fix them before release.
Background & Context
- Snapshots ship roughly once a week during active development and are enabled through the "Latest snapshot" toggle in the official launcher.
- The content here was being developed toward a future 1.21.x / 1.22 release; individual features may have been adjusted, renamed, or removed before that version shipped.
- Always keep a backup of important worlds before changing versions; the Astroworld versions database tracks client and server compatibility for 25w10a.
Frequently Asked Questions
When was Minecraft 25w10a released?
Minecraft 25w10a was released on March 5, 2025 as a weekly development snapshot for Minecraft: Java Edition.
What is new in 25w10a?
Added test block for map makers and technical improvements. Test blocks can run game tests and validate contraptions. Notable entries include: Added test block; Test block can run game tests for map validation; Useful for data pack and map development. In total it documents 5 changes across 2 categories.
Should I use 25w10a on my main world?
No. 25w10a is a weekly development snapshot meant for testing. Keep your main world on the latest stable release and only open a backup copy in a separate test world to try the new content.
Can I run 25w10a on a Minecraft server?
It is not recommended for a public server. Snapshot only - do not use in production. Use a private staging instance to test plugins and mods, not to host players.
Which Minecraft version is 25w10a a preview of?
25w10a is part of the development cycle for a future 1.21.x / 1.22 release. Features shown here are still in progress and may change before the final release.
Are there known issues in 25w10a?
Yes. Documented issues for this build include: Test block is operator-only and not accessible in survival. Development builds are expected to have rough edges that get fixed before release.
Looking for version compatibility info?
Check client and server version details on our versions database.