Build better apps, faster.

Realm’s mobile database is an open source, developer-friendly alternative to CoreData and SQLite. Start in minutes, port your app in hours, and save yourself weeks of work.

Available for Swift, Objective-C, Java, Kotlin, C#, and JavaScript.

Why Use Realm


Intuitive to Developers

Realm’s object-oriented data model is simple to learn, doesn’t need an ORM, and lets you write less code.


Designed for Offline Use

Realm’s local database persists data on-disk, so apps work as well offline as they do online.


Built for Mobile

Realm is fully-featured, lightweight, and efficiently uses memory, disk space, and battery life.

Streamline Your Code

Realm was built for mobile developers, with simplicity in mind. The idiomatic, object-oriented data model can save you thousands of lines of code.

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Live Objects:
Build Reactive Apps

Realm’s live objects mean data updated anywhere is automatically updated everywhere. If you need to freeze elements of your data for Reactive frameworks, you can do that, too.

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Fully Encrypted

Data can be encrypted in-flight and at-rest, keeping even the most sensitive data secure.

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Fast Querying

Lazy loading and a zero-copy architecture mean complex queries complete in microseconds.


Use a single database to build all your apps, on any major platform. Mobile, desktop and IoT.

Open Source

Realm is distributed under the Apache 2.0 license and backed by MongoDB.

Data Sync

The MongoDB Realm Sync service makes it simple to keep data in sync across users, devices, and your backend in real-time.

Developers Love Realm

100k+ developers have built their apps on Realm, with more than 50k+ stars on GitHub.

"A colleague brought the Realm Database to my attention, and I immediately fell in love with it. The whole schema is code and it just fit with how we were thinking."

Isaac Overacker
Software Architect, CBT Nuggets

"I boosted my database of 200,000 rows search from 7 seconds to 0.5 seconds with Realm. Practically under 30 mins of using it 1st time."

Vijaya P. Kandel
iOS Engineer

"Very impressive! I’m a huge fan of innovative solutions — especially critical processes like data persistence."

Kevin Hoctor
Software Engineer, Apple