RxDB

B tier on Embedded DatabasesScore 7.5 · #4 of 31

Android app: Yes
Free plan: Yes
Paid plans from: $99/mo
Runs on: Android, api, iOS, Linux, Mac, self-hosted, Web, Windows

rxdb.info

Summary

RxDB is a JavaScript NoSQL database that runs inside an app and stores data locally on the client. It supports offline operation, including deployments that work without a backend, and its Sync Engine can synchronize with services such as GraphQL, Firebase, Supabase, MongoDB, CouchDB, and others. Observable queries update when stored data changes. RxDB runs in browsers, mobile and desktop apps, and servers; its documented storage options include IndexedDB, OPFS, SQLite, LocalStorage, and MongoDB. Collections use JSON Schema with validation and migration support, and a password-based encryption plugin works in browsers, React Native, and Node.js. The free Apache 2.0 tier permits up to 13 open collections at once and includes community support through GitHub and Discord. Pro costs $99/mo (annual), and Pro Plus is $239.00 USD per month billed annually. Enterprise has a custom commercial license and a support SLA with a 24-hour first response. Deployed apps do not send user requests to an RxDB server. LocalStorage is intended for very small datasets, not heavy writes.

Who it is for

RxDB may suit JavaScript developers building offline-capable apps that need local data storage and optional synchronization. Teams needing a larger collection allowance, added features, or an Enterprise support SLA can consider its paid tiers.

What is good

Supports offline operation, including without a backend.
Observable queries update as stored data changes.
JSON Schema validation and migrations are supported.
Password-based encryption is available across several runtimes.

What to know first

Free tier allows up to 13 open collections at once.
No free trial is listed.
LocalStorage is not suited to large datasets or heavy writes.
Pro starts at $99/mo (annual).

Verdict

RxDB combines local-first storage with synchronization options and support for multiple runtimes. Check the free collection limit and storage requirements, especially if considering LocalStorage for substantial data.

RxDB plans and pricing

All plans

Free Free forever RxDB core · replication and realtime sync · default storages · up to 13 open collections · community support rxdb.info · 2 Oct 2026

Pro $99/mo annually, unlimited developers OPFS · IndexedDB · SQLite · Filesystem · WebCrypto Encryption · Fulltext Search rxdb.info · 2 Oct 2026

Pro Plus $239/mo annually, unlimited developers Worker and Shared Worker storage · Sharding · Memory-Mapped · optimizers · Fastify/Koa adapters · Sentry-compatible logger rxdb.info · 2 Oct 2026

Enterprise Not published custom commercial license · named engineer · 24-hour first-response SLA · architecture review · priority fixes · source-code access rxdb.info · 2 Oct 2026

Compared on embedded databases

Free plan: Yesrxdb.info
Paid from: $99/morxdb.info

Facts

Product: RxDB is a NoSQL database for JavaScript that runs directly in an app.rxdb.info · 2 Oct 2026
Offline-first: RxDB stores data locally on the client, supports offline operation, and can run entirely without a backend.rxdb.info · 2 Oct 2026
Synchronization: Its Sync Engine supports realtime synchronization with backends including RxServer, GraphQL, Firebase, Supabase, MongoDB, NATS, HTTP, CouchDB, WebRTC, Appwrite, Google Drive, and Microsoft OneDrive.rxdb.info · 2 Oct 2026
Reactivity: RxDB provides observable realtime queries that update when stored data changes.rxdb.info · 2 Oct 2026
Runtimes: RxDB runs in browsers, mobile apps, desktop applications, and servers.rxdb.info · 2 Oct 2026
Storage: Documented storage options include LocalStorage, IndexedDB, OPFS, Memory, Node.js Filesystem, SQLite, Expo Filesystem, Dexie.js, MongoDB, DenoKV, and FoundationDB.rxdb.info · 2 Oct 2026
Schema: RxDB uses JSON Schema for collections, with schema validation and migration support.rxdb.info · 2 Oct 2026
Encryption: The encryption plugin encrypts locally stored documents with a password and works in browsers, React Native, and Node.js.rxdb.info · 2 Oct 2026
License: The free tier is under the Apache 2.0 license.rxdb.info · 2 Oct 2026
Free limit: The Free tier allows up to 13 open collections in parallel.rxdb.info · 2 Oct 2026
Support: Free users receive community support through GitHub and Discord, while Enterprise includes a support SLA with a 24-hour first response.rxdb.info · 2 Oct 2026
Production privacy: Deployed applications do not make requests from users to an RxDB server, and the premium plugins contain no tracking code.rxdb.info · 2 Oct 2026
Small datasets: The LocalStorage storage is intended for simple browser setups and very small datasets and is not optimized for large data or heavy writes.rxdb.info · 2 Oct 2026