Differences between Unity and Unreal

A detailed summary of things making these engines different.

Updated over 3 years ago

Let's rephrase here a fundamental question.

I'm considering using Unreal, but many people seem to be using Unity for making indie games. I'm never planning to go into AAA games, I only want to make indie games as a solo developer(maybe in a small team). Is Unreal the right choice for me? Does Unreal have significant disadvantages compared to Unity for an indie dev or a small team? Is it slower/harder to make prototypes and small indie games in Unreal? Why do so many people use Unity instead?

This is just a short summary which should give you some basic overview, so you would know better what to look at. It aims to clarify some doubts and myths.

Unity is great for 2D games, mobile games

  • Unity shines at mobile development, lightweight on phones. Small engine footprint, even now possible to embed the Unity app in another app.

  • Unity now supports every mobile monetization method possible (ads, in-app purchase) - they focused for years on it.

  • Unity is much better for 2D games. Unreal support is very limited, it has only Paper 2D plugin. Yes, a single plugin and nothing around in the engine is designed with 2D in mind. Even the orthographic camera doesn't fully work with Unreal's lightning. Meanwhile, Unity provides a lot: 2D lightning, animation tools, sprites, tilemaps. Read more about the evolution of 2D tools in Unity.

  • Lightweight mobile games is a major reason why there are more Unity games published than Unreal ones. There are over 4 million apps on App Store alone.

  • Unity is all about being "simple, easy to start and universal".

UE4 is designed for small teams

This is the myth the Unreal Engine is meant for large studios. It's essential to debunk it here.

UE4 was designed with indie teams in mind as Epic already filled the "AAA studio niche" as it was possible at a time. That's why we have blueprints, visual scripting and dozens of tools working with each other out of the box. Especially if somebody working on a game when gameplay uses characters or heavily-directed content (implementing and scripting small things in every place of the game instead of relying on programmer every day).

Unreal rendering focuses on physically-based rendering and perspective camera. Making stylized games still possible, there are dozens of small stylized games done in UE4. You can make a racing game or spacecraft simulation game, the engine doesn't focus on FPS games (it's not UE3).

It comes with a lot of tools out of the box for handling characters, skeletal animations (not limited to humanoids), rendering such things as hair, fur and eye shaders. It's extremely indie-friendly in this regard.

It's already a tradition that Epic post a blog post with a list of stunning indie games developed with UE4 after major showcase events

Check examples of solo devs and small studios utilizing the engine - links to blog posts on the official blog.

And engine scales well from relatively small projects to AAA heavily modifying renderer.

How much these engines cost?

  • Unreal Engine is now free to use. And you don't pay anything until you reach the first $1 million game revenue! Check FAQ with links to licensing terms.

  • Unity's personal license is free, but it comes with some limitations. Check their plans and pricing.

Tools & learning curve

  • Unity's easier to start with. It's much simpler, fewer systems and features than UE4, it's easier to comprehend. Although it's not easier for non-programmers who want to script anything, it doesn't come with visual scripting out of the box.

  • There's less learning of Unity since this engine doesn't provide reach gameplay framework out of the box. The built-in Unreal gameplay framework is used commonly to create games focusing on characters. First-person perspective, third-person view, but also top-down. It simply comes with character movement, character-oriented camera manager, advanced animation system.

  • This previous point doesn't matter much if your game doesn't utilize 3D characters. Or you prefer to establish your own gameplay framework from scratch - "make engine your own".

  • The issue can arise in Unity if you'd like to do implement a complex game. It's often harder with Unity if working solo or in a small team. Keep in mind, we're not talking about "AAA complex level" - such division doesn't truly exist. There are no "indie features" or "AAA features". Every project uses a different set of features. You might not need 90% of Unreal features, but you might need all complexity and flexibility of a single system, i.e. Sequencer - saving a lot of time and effort while working on animating things in your world.

  • Unreal provides AAA tools for many domains out of the box. It's relatively easy to work with PBR-based tools and achieve "AAA indie" quality. The engine comes with visual scripting and many similar node-based editors. The list of tools and features provided with the vanilla engine is really long...

  • The skeletal animation system is extensive and provides a lot of tools to non-programmers. Working with animation is sweet, i.e UE4 is the common choice for fighting/action games. A new Control Rig system allows for procedural authoring animation just in the engine; also possible to keyframe animation through Sequencer and bake the result to animation asset. Learn how to create a character animation rig with Control Rig Mannequin sample.

  • There are no "must-have" plugins for Unreal Engine to get from its marketplace. Engine plugins serve as workflow improvements or providing features for a specific type of project.

  • It makes UE4 very friendly for artists and designers. The engine philosophy is to provide all the standard tools out of the box. That's why it's so huge piece of software and it can be intimidating for beginners. You don't need to learn everything, just learn what you need for a given game. And you don't programmer to start since you got node-based editors everywhere in the engine.

  • Unreal Engine 5 promises to bring huge workflow updates to 3D artists. No more retopology of meshes, creating a low-poly version, generating LODs and baking normal maps.

  • Having so many systems and tools out of the box, sometimes you might feel forced to do things in the "Unreal way". That's sometimes some issue for developers/projects working on unconventional projects, or when doing things in a way designed by Epic engineer happens to be confusing.

  • Now, Unity is in process of adding fundamental tools to the vanilla engine, i.e. visual shader editor, input management. That's why the Asset Store was so vital for Unity through the years as the engine was missing so many things. Still, there's no visual scripting - Unity acquired Bolt as a temporary solution, but their native solution isn't ready yet.

  • Unity's strength is flexibility in customizing rendering, how the render passes are arranged. It's improved with new Scriptable Rendering Pipelines - High Definition Render Pipeline and Universal Render Pipeline. This is much harder with UE, it's required to dive into C++ and modification of the engine code.

  • Nobody uses Unity's networking (they working on a brand new solution), relying on third-party solutions. Meanwhile, UE4 comes with the excellent multiplayer support out of the box. Unreal's gameplay framework is built with networking in mind. Gameplay Ability system is a specialized plugin preventing you from reinventing the wheel while building multiplayer mechanics.

Programming

Unity is friendly for programmers.

  • C# is easier to learn than C++, it feels mostly like a general-purpose scripting language in Unity.

  • If you don't get the basics of programming yet, it might be very efficient to start learning programming for video games from Unity with C#. It would smoothly introduce you to coding and teach basic concepts. This might be recommended even if you plan to work with Unreal later - much easier to grasp Unreal C++ after that. And you would understand what you're doing in blueprints - sadly, official docs and many popular Youtube tutorials on blueprints don't explain programming concepts, so your blueprint code quickly gets messy.

  • Visual Studio works nicely with C# while editing C++ can be very cumbersome without proper plugins.

  • Both engines support Visual Studio Code, although that's rarely used in bigger studios.

  • Rider IDE supports Unity and C# for some time. Support for Unreal is coming, we have Preview for now.

People are often scared of learning C++ in UE4.

  • It comes from the fact that pure C++ requires a lot of low-level knowledge, taking care of cleaning up memory, assembling build toolchain.

  • The thing is you don't use pure C++ with UE4, the same way you don't use pure C# with Unity. Thanks to that writing C++ code for UE4 is much, much easier than regular C++. Actually, it's more similar to Unity's C#.

  • Read the wiki page about Unreal C++ to learn more :)

Stability of technology

  • Unity company doesn't create its own games. You can feel it this engine isn't used daily by the internal team working on complex games. Meanwhile Epic dog foods every single system. Either with Fortnite - systems and editor tools tested game played by hundreds of millions of people on every major platform. If Fortnite doesn't use specific systems, they build an extensive demo or small game (i.e. Robo Recall for VR). And this might the most important thing, Unreal tools are proven and often simply work. Even if marked as "beta".

  • It's important to note that many Unity developers recommend using LTS (Lont Term Support) releases of engine for production. Instead of so-called "tech releases", which are introduced a lot of changes, new systems and tools - but often quite unstable for use in development.

  • Unity does usually create a promotional movie and doesn't even release it as a project - it's confirmed that some demos used renderer features that weren't implement in the engine afterward. For these reasons, we haven't ever seen a game that looks as good as Unity's internal demo. This is a weird strategy.

  • A lot of indie studios switch from Unity to UE4 for the next project because Unity wasn't enough for more ambitious projects: more content, higher visual fidelity, more power for non-programmers, easier prototyping. A notable example would be InXile switching to Unreal for the next RPG after Wastelands 3.

  • Unity is in process of upgrading the entire engine for bigger projects and teams, but this an enormous undertaking... It's basically "Unity 2nd generation", but changes are integrated into current Unity. It means the engine goes through huge architectural changes and some studios decide Unity is too unstable to develop 3D games for now. This is Reddit discussion under the opinion of Rust creator on the current state of Unity.

Unreal editor requires a better hardware

  • The Unity editor has low hardware requirements, but it won't run much faster on beefy hardware. It's great to make small games on a laptop, bring it to co-worker space or anywhere. Not so great for projects with a lot of code and assets, Unity won't scale that well.

  • UE4 requires more powerful hardware as it targets 3D games. It might get expensive if you're about developing the hi-end 3D game on a laptop. Check the article on Recommended Hardware for UE4. In return, the engine handles asset-heavy projects way better than Unity. As engine targeting AAA since the beginning of time - it's optimized for crunching gigabytes of content. Engine fully utilizes even 128 thread CPU for things like code compilation, shader compilation, cooking game. Now Epic is in process of upgrading engine for open worlds, that already brings performance and workflow benefits for smaller teams.

  • It's a huge productivity boost to use two screens with Unreal editor. It wasn't optimized to use on a single screen with resolution lower than Full HD.

For beginners

Youtube engine comparisons tend to overgeneralize, saying "both engines have 3D tools, thus are similar". And actually providing very little information, but... this one is a really good comparison from the perspective of a beginner\!