How do I open multiple Level Blueprints at the same time?

I’m trying to open multiple Level Blueprints at the same time so I can compare them, but whenever I switch to a different level Unreal Engine closes the blueprint of the level I’m leaving.

Hello friend,
You will need to open other instances to see the multiple levels, or add the levels on your world map and see one and other.

You can manage multiple levels to see them and compare on this way:

There’s a discussion about this here too:

I hope it helps.

By the way, I think I just did this another way by accident. If you do a project wide “Find in blueprints” for a variable that exists on a different level blueprint, then double click the result, it opens that level blueprint without opening the level (and doesn’t close anything). Then you can copy-paste stuff across easily


This just saved me a huge headache, thanks! I think I found a bug in UE 5.0.3 where with some combination of World Partition + level Blueprint referencing an editor only actor the editor was crashing when I’d open the level. To fix I used @Friend_of_Ants’s approach to search for something I knew was in the level BP, opened it, removed the bad reference, and then I could open the level.

For searchability, the logs for this crash were:

Assertion failed: Pair != nullptr [File:D:\build++UE5\Sync\Engine\Source\Runtime\Core\Public\Containers\Map.h] [Line: 656]
A breakpoint instruction (__debugbreak() statement or a similar call) was executed in UnrealEditor-Win64-DebugGame.exe.
Exception thrown: read access violation.
ActorDescView was 0x10.

The last frame in the Call Stack was:


5.0.3 has some bugs with world partition. It fails to unload tiles causing crashes due to basically filling up memory with traveled distance to new plots of land.
5.1 fixes this., perhaps they also patched your above situation.

You can just run the editor a second time if you want.

Otherwise, only way I know of is to make them all sublevels of another level, and then you can view them at once

Two simultaneous ooe editors is asking for trouble. You will start to get asset save errors. Unreal doesn’t handke 2 at once well.

Definitely true if you’re messing around with things, but if your goal is to look at two different things that you can’t normally open together, it works reasonably well.