Firebase vs Socket.IO

Discover how Firebase compares to Socket.IO, and understand which is right for your use case, based on dimensions such as core features, pricing, reliability, and scalability.

What is Firebase?

Firebase is a cloud-native backend by Google that allows developers to build mobile and web applications. Firebase services include Firebase Realtime data, Firestore database, authentication, and Firebase Cloud Messaging (FCM), among others.

When to use Firebase

Pros and cons of Firebase

What is Socket.IO?

Socket.IO is a library created in 2010 that provides realtime, bi-directional communication between clients and servers. It allows the management of connections, sending and receiving messages, and more. Built on top of the WebSocket protocol, it provides additional capabilities compared to raw WebSockets. WebTransport (a WebSocket alternative) is also supported.

When to use Socket.IO

Pros and cons of Socket.IO

Compare Firebase and Socket.IO

Let’s compare Firebase and Socket.IO, looking at key dimensions such as their core features, pricing, integrations & interoperability, quality of service, performance & availability and security & compliance.

Disclaimer: This comparison was created based on documentation and resources freely available online about Firebase and Socket.IO. The content was last updated on 16 May 2025 for Firebase and on 24 Apr 2025 for Socket.IO. Be sure to double-check everything before you make any decisions. If you do find anything incorrect or out of date, then please let us know.

Alternatives to Firebase and Socket.IO

While both Firebase and Socket.IO are worth considering as options for realtime experiences, they aren’t without their limitations. We suggest evaluating them against the following alternatives to make sure you find the right solution for your needs.

Alternatives to Firebase

Supabase Realtime is a globally distributed real-time server network built on PostgreSQL, enabling developers to build applications with real-time data sync.

Pusher is a first-generation pub/sub messaging service that provides bi-directional hosted APIs for adding realtime features to applications.

OneSignal is a customer engagement platform that offers push notifications, messages, and email sends for businesses to manage communication with their users.

See more alternatives to Firebase

Alternatives to Socket.IO

Azure SignalR is an Azure-hosted, fully managed realtime framework built on top of an open-source software library for Microsoft ASP.NET.

Firebase Realtime Database is a cloud-hosted database by Google, allowing developers to build realtime applications for web and mobile.

PubNub is a developer API platform that powers the realtime infrastructure in apps to build engaging Virtual Spaces where online communities can connect.

See more alternatives to Socket.IO

Discover how Firebase and Socket.IO stack up against Ably

Ably is the definitive realtime experience platform of the internet. See how we compare to Firebase and Socket.IO on key dimensions such as core features, pricing, integrations, QoS, performance, and security and compliance.

Ably vs Firebase Ably vs Socket.IO

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Ably has built reliable realtime infrastructure so you don’t have to. On our free plan you benefit from:

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200 concurrent connections

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	Firebase	Socket.IO	Why this matters
Core features
Pub/Sub messaging	Reduces communication code complexity, simplifying the process of building highly functional and architecturally complex realtime apps.	Firebase Partial Firebase does not natively support Pub/Sub messaging. However, this can be implemented with Google's Pub/Sub service. Read more	Socket.IO No Need to rely on a third party - e.g. use a Redis adapter to broadcast events to clients through the Redis pub/sub mechanism. Read more	Reduces communication code complexity, simplifying the process of building highly functional and architecturally complex realtime apps.
Chat capabilities	Accelerates the time to implement rich chat experiences with features such as read receipts, typing indicators, and more.	Firebase Yes You can build chat capabilities on top of Firebase's Realtime Database.	Socket.IO Partial As it's a library, you need to create the chat capabilities yourself. But this can be done using Socket.IO.	Accelerates the time to implement rich chat experiences with features such as read receipts, typing indicators, and more.
Collaboration capabilities	Enables you to quickly integrate realtime collaborative features like live cursors, member location, avatar stacks, and component locking.	Firebase Yes	Socket.IO Partial As it's a library, you need to implement collaboration capabilities yourself. But you can do this using Socket.IO itself.	Enables you to quickly integrate realtime collaborative features like live cursors, member location, avatar stacks, and component locking.
State sync capabilities	Enables realtime data synchronization across devices and users, ensuring a cohesive and up-to-date user experience.	Firebase Yes The Firebase Realtime Database lets you store and sync data between your users in real time. Read more	Socket.IO No The library does not support this. You would need to create a bespoke state sync capability or integrate a third party library to get state synchronisation.	Enables realtime data synchronization across devices and users, ensuring a cohesive and up-to-date user experience.
Presence	Maintaining a view of which users are connected, and their associated metadata, enables their online status to be updated in realtime.	Firebase Yes Firebase Realtime Database natively supports presence. Read more	Socket.IO Partial It is the duty of your application to link a Socket.IO connection to a user account. Read more	Maintaining a view of which users are connected, and their associated metadata, enables their online status to be updated in realtime.
Occupancy	High-level metrics about the clients currently connected to a channel make it simple to show things such as connected user count, or display which channels are the most popular.	Firebase Partial Firebase does not have built-in support for occupancy tracking. However, occupancy tracking functionality can be built on top of the Firebase Realtime Database.	Socket.IO Partial Rooms are available. It is possible to query for rooms and SIDs. See more	High-level metrics about the clients currently connected to a channel make it simple to show things such as connected user count, or display which channels are the most popular.
Message interactions	Enables interaction with previously-sent messages, facilitating the implementation of features like message reactions and threads.	Firebase Partial Message interactions are not natively supported in Firebase. However, you can programmatically build interactions on top of Firebase's Realtime Database.	Socket.IO Partial You would need to build the message interaction functionality yourself on top of Socket.IO. Learn more	Enables interaction with previously-sent messages, facilitating the implementation of features like message reactions and threads.
Message history	Enables clients to catch up on missed messages when inactive, ensuring a user doesn’t miss any important messages.	Firebase No	Socket.IO No The Socket.IO server does not store messages. Your application has to persist messages somewhere for the clients that are not currently connected. Learn more	Enables clients to catch up on missed messages when inactive, ensuring a user doesn’t miss any important messages.
Push notifications	Cross-platform push notifications make it possible to deliver important and timely messages to users even when they’re inactive.	Firebase Yes You can create, send, and monitor push notifications using Firebase Cloud Messaging. Read more	Socket.IO No Socket.IO not support Push notifications. You would need to build this capability yourself and/or use another library. Learn more	Cross-platform push notifications make it possible to deliver important and timely messages to users even when they’re inactive.
Message delta compression	Minimizes bandwidth and can reduce latency, particularly in scenarios where continuous updates are sent.	Firebase No	Socket.IO No	Minimizes bandwidth and can reduce latency, particularly in scenarios where continuous updates are sent.
Programmatic management	Enables the automation of provisioning, management, and testing of service resources, simplifying integration with existing development workflows such as CI.	Firebase Yes Firebase projects can be managed programmatically using the Firebase Management API.	Socket.IO Yes The Socket.IO server is initialised in code. It is possible to configure the socket.IO server's configuration in code as well. Learn more	Enables the automation of provisioning, management, and testing of service resources, simplifying integration with existing development workflows such as CI.
Pricing
Free plan	With a free plan, you can test the service’s functionality and compatibility with your project before committing to a paid plan.	Firebase Yes The Spark plan (free plan) realtime database is limited to 100 simultaneous connections and 1 GB of storage. Read more	Socket.IO Yes Open Source framework that uses the MIT license.	With a free plan, you can test the service’s functionality and compatibility with your project before committing to a paid plan.
Pricing model	The pricing model should align with your project's expected load, usage patterns, and budget in order to be cost-effective and efficient.	Firebase Firebase offers a pay-as-you-go pricing plan, called Blaze, based on the services you use and the amount of unit costs incurred. Firebase pricing is usage-based, with most services charging per read, write, storage, and bandwidth. There are two main realtime database options, and other tools that can impact cost depending on your app architecture. Read more	Socket.IO Free and open-source.	The pricing model should align with your project's expected load, usage patterns, and budget in order to be cost-effective and efficient.
Pricing plans	The pricing plans offered by cost.	Firebase Free (Spark) plan: Limited to 100 simultaneous connections and 1 GB of storage. PAYG (Blaze) plan: 1 GB of storage is priced at $5. Supports multiple databases per project.		The pricing plans offered by cost.
Integrations & interoperability
SDKs	Supporting multiple languages and platforms offers greater flexibility when building cross-platform realtime apps.	Firebase iOS Android Web C++ Unity	Socket.IO Client and Server APIs only. C++ Swift Java Javascript Typescript Node.js Python Golang Rust Dart .NET Kotlin	Supporting multiple languages and platforms offers greater flexibility when building cross-platform realtime apps.
Supported realtime protocols	Support for multiple protocols provides the flexibility to choose a protocol that best suits your project’s requirements.	Firebase WebSockets Server-sent events (SSEs)	Socket.IO WebSocket WebTransport HTTP	Support for multiple protocols provides the flexibility to choose a protocol that best suits your project’s requirements.
Serverless functions	Enables integration with third-party cloud providers by facilitating the execution of custom code against messages to perform business logic like on-the-fly translation.	Firebase Firebase supports serverless functions through Cloud Functions for Firebase. Read more	Socket.IO No It is not possible to trigger serverless functions with Socket.IO on it's own. See this Reddit post for more info	Enables integration with third-party cloud providers by facilitating the execution of custom code against messages to perform business logic like on-the-fly translation.
Streaming & queueing	Provides a dependable method to reroute messages from the service to third-party streams and queues for further processing.	Firebase Yes	Socket.IO No Socket.IO does not offer native queues and streaming.	Provides a dependable method to reroute messages from the service to third-party streams and queues for further processing.
Observability services	Enables realtime monitoring and troubleshooting by offering insights into service behavior directly in your observability platform of choice.	Firebase Yes Using Firebase Performance Monitoring you can monitor your application performance based on location, device, or version.	Socket.IO Yes The Socket.IO admin UI can be used to have an overview of the state of your Socket.IO deployment.	Enables realtime monitoring and troubleshooting by offering insights into service behavior directly in your observability platform of choice.
CI/CD tools	Makes it possible to provision and configure service infrastructure as part of a CI or CD pipeline, enabling repeatable and reliable deployments.	Firebase Yes Supports: Jenkins Buddy CI/CD Google Cloud Build GitHub Workflow	Socket.IO No	Makes it possible to provision and configure service infrastructure as part of a CI or CD pipeline, enabling repeatable and reliable deployments.
Quality of Service
Scalability	Scalability is vital as it ensures the service can handle increased data load or users without compromising performance.	Firebase Firebase is limited to 200k simultaneous connections (100 for Spark plan), 1000 Cloud Functions per write (500 for v2 per region), 1 MB event size, and 10 MB/sec data transfer to Cloud Functions.	Socket.IO No published metrics. Socket.IO servers don’t communicate between them, so you need a way to route events to all clients, even if they are connected to different servers. This is made possible by using adapters, of which the Redis adapter seems to be the most popular choice.	Scalability is vital as it ensures the service can handle increased data load or users without compromising performance.
Guaranteed message delivery	Ensures messages are never lost during transmission, even in the presence of network disruptions.	Firebase No	Socket.IO Partial By default, Socket.IO provides an "at most once" guarantee of delivery. From the client side, you can achieve an at least once guarantee with acknowledgements and timeouts.	Ensures messages are never lost during transmission, even in the presence of network disruptions.
Guaranteed message ordering	Maintains the sequence of messages as they were sent. This is particularly important in apps where the chronological order of messages is essential for meaningful communication.	Firebase No	Socket.IO Yes Socket.IO guarantees ordering, no matter which low-level transport is used. Read more	Maintains the sequence of messages as they were sent. This is particularly important in apps where the chronological order of messages is essential for meaningful communication.
Exactly-once message delivery	Guarantees that each message is processed exactly once, preventing data inconsistencies that can arise from duplicate processing or missing messages.	Firebase No	Socket.IO No At least once or at most once only.	Guarantees that each message is processed exactly once, preventing data inconsistencies that can arise from duplicate processing or missing messages.
Performance & availability
Uptime Guarantee	An uptime guarantee instills confidence in the reliability of the service and protects your business from the negative impacts of downtime.	Firebase 99.95%. Read more	Socket.IO No It is a library, not a platform.	An uptime guarantee instills confidence in the reliability of the service and protects your business from the negative impacts of downtime.
Global edge network	By bringing servers (Points of Presence, or PoP) geographically closer to the devices of end users, and routing requests to the nearest PoP, global latency is reduced to a minimum.	Firebase Yes Firebase's global CDN (content delivery network) supports a global edge network by integrating with Google Cloud Platform (GCP), with edge PoPs spanning over 180 internet exchanges and over 160 interconnection facilities worldwide. Read more	Socket.IO No	By bringing servers (Points of Presence, or PoP) geographically closer to the devices of end users, and routing requests to the nearest PoP, global latency is reduced to a minimum.
Multi-region data replication (message durability)	By replicating data across multiple regions, the risk of data loss or downtime is greatly mitigated since if data is lost or a server fails in one region, the information can be retrieved from another.	Firebase Partial Firebase supports multi-region data replication, primarily through Cloud Firestore locations, but this is not supported in Firebase Realtime Database. Read more	Socket.IO No	By replicating data across multiple regions, the risk of data loss or downtime is greatly mitigated since if data is lost or a server fails in one region, the information can be retrieved from another.
No single point of failure or congestion	Having no single point of failure means a system is resilient and can continue to operate even if one part fails. Avoiding a single point of congestion ensures messages flow efficiently across the system and avoids bottlenecks that could lead to performance issues under load.	Firebase Yes Firebase's design uses Google Cloud Platform's infrastructure, which implements redundancy and automatic failover features.	Socket.IO No As Socket.IO is a library, the implementation of it dictates points of failure and congestion.	Having no single point of failure means a system is resilient and can continue to operate even if one part fails. Avoiding a single point of congestion ensures messages flow efficiently across the system and avoids bottlenecks that could lead to performance issues under load.
Latency	Low latency is crucial for realtime apps as it ensures swift and efficient data transmissions, providing a smoother and more responsive user experience.	Firebase Unknown.	Socket.IO Unknown	Low latency is crucial for realtime apps as it ensures swift and efficient data transmissions, providing a smoother and more responsive user experience.
Security & compliance
API key authentication	Simplifies the authentication code on trusted servers compared to requesting, managing, and refreshing tokens.	Firebase Yes	Socket.IO No	Simplifies the authentication code on trusted servers compared to requesting, managing, and refreshing tokens.
Token-based authentication	Provides a means to securely authenticate user devices against your user management system.	Firebase Yes Supported with JSON Web Tokens (JWTs). Read more	Socket.IO No No native Token based auth. It is possible to use middlewares.	Provides a means to securely authenticate user devices against your user management system.
Single Sign-On (SSO) authentication	SSO streamlines login processes, boosts security by minimizing password use, and meets compliance needs for secure data access management.	Firebase Yes SSO in a Firebase application can be implemented using SAML (Security Assertion Markup Language). Read more	Socket.IO No No native SSO. It is possible to use middlewares.	SSO streamlines login processes, boosts security by minimizing password use, and meets compliance needs for secure data access management.
Rules for permissions and operations	Provides control over which users can subscribe and publish to certain channels.	Firebase Yes Using Firebase Realtime Database Security Rules you can set who has access to your database. Read more	Socket.IO No	Provides control over which users can subscribe and publish to certain channels.
End-to-end encryption	Ensures that the data transmitted between the client and the API server remains confidential and secure while in transit.	Firebase No Data in transit is encrypted using HTTPS in all Firebase services, but this does not include end-to-end encryption. Read more	Socket.IO No	Ensures that the data transmitted between the client and the API server remains confidential and secure while in transit.
Encryption at rest	Ensures data stored by the service is secure and compliant, while also mitigating the risks of a data breach.	Firebase Partial Some Firebase services are encrypted at rest while others are not. Firebase Realtime Database and Firebase Cloud Messaging are encrypted at rest. Read more	Socket.IO No	Ensures data stored by the service is secure and compliant, while also mitigating the risks of a data breach.
Compliance	Compliance with regulations can impact your ability to meet legal obligations in your industry.	Firebase Firebase ensures compliance with international and industry standards for security and privacy standards including: GDPR CCPA ISO 27001 SOC 1 SOC 2 SOC 3 Read more	Socket.IO None.	Compliance with regulations can impact your ability to meet legal obligations in your industry.