Best Free Offline-First Databases

Firebase helps you build and run successful apps. Backed by Google and loved by app development teams - from startups to global enterprises. Products and solutions you can rely on through your app's journey. Install pre-packaged, open-source bundles of code to automate common development tasks. Easily integrate Firebase with your team’s favorite tools. Use Firebase products together to solve complex challenges and optimize your app experience. Personalize your onboarding flow, grow user engagement, or add new functionality with Firebase. Firebase provides detailed documentation and cross-platform SDKs to help you build and ship apps on Android, iOS, the web, C++, and Unity. Learn how to create a Firebase project, register apps to it, and integrate the Firebase SDKs for your products and platform: iOS, Android and Web. Learn about Firebase projects, including concept overviews, deep-dives into topics like project permissions and project management tools, or preparing to launch your app.

SQLite is a C-language library that implements a small, fast, self-contained, high-reliability, full-featured, SQL database engine. SQLite is the most used database engine in the world. SQLite is built into all mobile phones and most computers and comes bundled inside countless other applications that people use every day. SQLite is an in-process library that implements a self-contained, serverless, zero-configuration, transactional SQL database engine. The code for SQLite is in the public domain and is thus free for use for any purpose, commercial or private. SQLite is the most widely deployed database in the world with more applications than we can count, including several high-profile projects.

Cloud Firestore is a fast, fully managed, serverless, cloud-native NoSQL document database that simplifies storing, syncing, and querying data for your mobile, web, and IoT apps at global scale. Its client libraries provide live synchronization and offline support, while its security features and integrations with Firebase and Google Cloud Platform (GCP) accelerate the building of truly serverless apps. Firestore offers a great developer experience with built-in live synchronization, offline support, and ACID transactions. These features are available across a robust set of client and server-side libraries. Firestore automatically scales up and down based on demand. It requires no maintenance and provides high availability of 99.99–99.999% achieved through strongly consistent data replication. No-ops database lets you pay only for what you use—no up-front expenditure or underutilized resources. Simplified architecture lets your apps talk directly to Firestore.

​PouchDB is an open source JavaScript database inspired by Apache CouchDB, designed to run efficiently within the browser. It enables applications to store data locally while offline and synchronize it with CouchDB and compatible servers when back online, ensuring user data remains in sync across sessions. PouchDB supports cross-browser functionality, is lightweight, requires just a script tag and 46KB (gzipped) in the browser, and can be installed via npm. It is easy to learn, requiring some programming knowledge, and is fully open source, with development conducted openly on GitHub. PouchDB allows developers to build applications that function seamlessly offline and online, providing a consistent user experience regardless of network connectivity. It offers a simple API for creating, reading, updating, and deleting documents.

​RxDB is a local-first, NoSQL JavaScript database optimized for modern web and mobile applications. It enables offline-first functionality by storing data directly on the client using storage engines like IndexedDB, OPFS, SQLite, and more. RxDB offers real-time reactivity, allowing developers to subscribe to changes in documents, fields, or queries, ensuring that UI components update automatically as data changes. Its flexible replication engine supports syncing with various backends and custom endpoints. RxDB integrates seamlessly with frameworks and environments. Additional features include field-level encryption, schema validation, conflict resolution, backup and restore, attachments, and CRDT support. By reducing server load and providing low-latency local queries, RxDB enhances performance and scalability, making it ideal for applications that require real-time updates, offline access, and cross-platform consistency.

​IndexedDB is a low-level API for client-side storage of significant amounts of structured data, including files/blobs. This API uses indexes to enable high-performance searches of this data. While web storage is useful for storing smaller amounts of data, it is less useful for storing larger amounts of structured data. IndexedDB provides a solution. IndexedDB is a transactional database system, like an SQL-based Relational Database Management System (RDBMS). However, unlike SQL-based RDBMSes, which use fixed-column tables, IndexedDB is a JavaScript-based object-oriented database. IndexedDB lets you store and retrieve objects that are indexed with a key; any objects supported by the structured clone algorithm can be stored. You need to specify the database schema, open a connection to your database, and then retrieve and update data within a series of transactions. Like most web storage solutions, IndexedDB follows the same-origin policy.

Dexie.js is a minimalistic and bulletproof IndexedDB wrapper library designed to simplify client-side storage. At only ~29k minified and gzipped, it offers a concise API that addresses the complexities of native IndexedDB, such as ambivalent error handling, poor queries, lack of reactivity, and code complexity. Dexie.js provides a well-thought-through API design, robust error handling, extendability, change tracking awareness, and extended KeyRange support, including case-insensitive search, set matches, and OR operations. It embraces the IndexedDB specification and all its features, allowing developers to use existing IndexedDB data without the need for data migration. Dexie.js supports composable real-time queries, enabling components to mirror the database in real-time across various front-end frameworks like React, Svelte, Vue, and Angular. With Dexie Cloud, developers can build consistent, authenticated, and access-controlled local-first apps with just a few lines of extra code.

​WatermelonDB is a reactive database framework designed to build powerful React and React Native apps that scale from hundreds to tens of thousands of records while remaining fast. It ensures instant app launch regardless of data volume, supports lazy loading to load data only when needed, and offers offline-first capabilities with synchronization to your own backend. It is multiplatform. Optimized for React, it allows easy integration of data into components and is framework-agnostic, enabling the use of its JavaScript API with other UI frameworks. Built on a robust SQLite foundation, WatermelonDB provides static typing with Flow or TypeScript and optional reactivity through an RxJS API. WatermelonDB addresses performance issues in complex applications by loading nothing until requested and performing all querying directly on SQLite on a separate native thread, ensuring most queries resolve instantly.

​Realm is a mobile-first, open source object database designed to run directly inside phones, tablets, and wearables. It provides a simple, object-oriented data model that eliminates the need for an ORM, allowing developers to define models as regular classes in languages like Swift, Java, Kotlin, C#, JavaScript, Dart, and C++. Realm's architecture ensures high performance and low memory usage by employing a zero-copy design, lazy loading, and multi-version concurrency control (MVCC) for thread-safe operations. It's live objects and collections automatically update across threads, enabling reactive programming patterns. Realm supports relationships between objects via links and backlinks, facilitating complex data structures. Developers can utilize tools like Realm Studio to inspect and manipulate local Realm databases and integrate Realm into various platforms, including React Native, Flutter, Xamarin, and Node.js.

​OrbitDB is a serverless, distributed, peer-to-peer database that utilizes IPFS for data storage and Libp2p Pubsub for automatic synchronization across peers. It employs Merkle-CRDTs to ensure conflict-free database writes and merges, making it suitable for decentralized applications, blockchain integrations, and local-first web apps. OrbitDB offers various database types tailored to different use cases: 'events' for immutable append-only logs, 'documents' for JSON document storage indexed by a specified key, 'keyvalue' for traditional key-value pairs, and 'keyvalue-indexed' for LevelDB-indexed key-value data. All these databases are built atop OpLog, an immutable, cryptographically verifiable, operation-based CRDT structure. The JavaScript implementation supports both browser and Node.js environments, with a Go version maintained by the Berty project.

Use Core Data to save your application’s permanent data for offline use, to cache temporary data, and to add undo functionality to your app on a single device. To sync data across multiple devices in a single iCloud account, Core Data automatically mirrors your schema to a CloudKit container. Through Core Data’s Data model editor, you define your data’s types and relationships, and generate respective class definitions. Core Data can then manage object instances at runtime to provide several features. Core Data abstracts the details of mapping your objects to a store, making it easy to save data from Swift and Objective-C without administering a database directly. Core Data’s undo manager tracks changes and can roll them back individually, in groups, or all at once, making it easy to add undo and redo support to your app. Perform potentially UI-blocking data tasks, like parsing JSON into objects, in the background.

Berkeley DB is a family of embedded key-value database libraries providing scalable high-performance data management services to applications. The Berkeley DB products use simple function-call APIs for data access and management. Berkeley DB enables the development of custom data management solutions, without the overhead traditionally associated with such custom projects. Berkeley DB provides a collection of well-proven building-block technologies that can be configured to address any application need from the hand-held device to the data center, from a local storage solution to a world-wide distributed one, from kilobytes to petabytes.

Realtime, decentralized, offline-first, graph database engine. The data that needs to stored, loaded, and shared in your app without worrying about servers, network calls, databases, or tracking offline changes or concurrency conflicts. GUN is a small, easy, and fast data sync and storage system that runs everywhere JavaScript does. The aim of GUN is to let you focus on the data that needs to be stored, loaded, and shared in your app without worrying about servers, network calls, databases, or tracking offline changes or concurrency conflicts. This lets you build cool apps fast. GUN gives you the most powerful weapons of the internet — decentralization and real privacy — to reclaim the web and make it truly free and open. GUN is a data­base en­gine that runs every­where JavaScript does — browsers, mo­bile de­vices and servers, al­low­ing you to build ex­act­ly the data sys­tem you want.

FairCom EDGE simplifies the integration of sensor and machine data at the source – whether it’s a factory, water treatment plant, oil platform or wind farm. The world’s first converged IoT/Industrial IoT hub, FairCom EDGE unifies messaging, persistence and analytics with an all-in-one solution – complete with browser-based administration, configuration and monitoring. FairCom EDGE supports MQTT and OPC UA for machine-to-machine (M2M) communication, SQL for interactive analytics and HTTP/REST for real-time monitoring. It continuously retrieves data from sensors and machines with OPC UA support, and receives messages from those with MQTT support. The data is automatically parsed, persisted and made accessible via MQTT and SQL.

Unlike other NoSQL databases, Couchbase provides an enterprise-class, multicloud to edge database that offers the robust capabilities required for business-critical applications on a highly scalable and available platform. As a distributed cloud-native database, Couchbase runs in modern dynamic environments and on any cloud, either customer-managed or fully managed as-a-service. Couchbase is built on open standards, combining the best of NoSQL with the power and familiarity of SQL, to simplify the transition from mainframe and relational databases. Couchbase Server is a multipurpose, distributed database that fuses the strengths of relational databases such as SQL and ACID transactions with JSON’s versatility, with a foundation that is extremely fast and scalable. It’s used across industries for things like user profiles, dynamic product catalogs, GenAI apps, vector search, high-speed caching, and much more.

Ultrafast, scalable, embeddable SQL database with commercial-grade data security, disaster recovery, and change synchronization. Cross-platform, zero-install, embedded database as a direct-access library. Cross-platform, zero-install, embedded database with database-level and column-level AES and DES encryption. Concurrent applications/client access to the database on Windows with database-level and column-level AES and DES encryption. Ultrafast, scalable, SQL server database for Windows and Linux with commercial-grade data security, disaster recovery and change synchronization. Attacks on databases and loss of data can be costly and lead to loss of customers’ trust (and business), regulatory action, and heavy fines. InterBase provides over-the-wire and at-rest encryption, separate security login, and role-based user security. InterBase maintains full on-disk encryption while adding negligible overhead to database speed and performance.