Ably vs Socket.IO
Discover how Socket.IO compares to Ably, and understand which is right for your use case, based on dimensions such as core features, pricing, reliability, and scalability.
What is Ably?
Ably is a realtime experience platform that provides APIs and SDKs to power realtime functionality - with no realtime infrastructure to build and maintain. Our application building blocks and integrations enable developers to quickly create live experiences from live chat and data broadcast, to collaborative UXs and notifications.
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.
Compare Ably and Socket.IO
Let’s compare Ably and Socket.IO, looking at key dimensions such as their core features, pricing, integrations, QoS, performance, and security and compliance.
Disclaimer:This comparison was created based on documentation and resources freely available online about Ably and Socket.IO. The content was last updated on 1 Aug 2024 for Ably and on 26 Sept 2024 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 If you do find anything incorrect or out of date, then please contact us.
| Core features | |||
Pub/Sub messaging | Reduces communication code complexity, simplifying the process of building highly functional and architecturally complex realtime apps. | Ably Yes Ably provides robust pub/sub messaging capabilities over serverless WebSockets. | 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 |
Chat capabilities | Accelerates the time to implement rich chat experiences with features such as read receipts, typing indicators, and more. | Ably Partial It's possible to use Ably Pub/Sub to build chat applications today, as many customers do. A new product to make this seamless, idiomatic and help accelerate time-to-market is under active development. | Socket.IO Partial As it's a library, you need to create the chat capabilities yourself. But this can be done using Socket.IO. |
Collaboration capabilities | Enables you to quickly integrate realtime collaborative features like live cursors, member location, avatar stacks, and component locking. | Ably Yes The Spaces SDK provides an opinionated set of abstractions for collaborative environments including live cursors, avatar stacks and component locking. Learn more | Socket.IO Partial As it's a library, you need to implement collaboration capabilities yourself. But you can do this using Socket.IO itself. |
State sync capabilities | Enables realtime data synchronization across devices and users, ensuring a cohesive and up-to-date user experience. | Ably Yes Ably provides a self-hostable and managed database connector to stream updates over our serverless WebSocket platform. Ably also provides the Models SDK for seamless connector interactions. Learn 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. |
Presence | Maintaining a view of which users are connected, and their associated metadata, enables their online status to be updated in realtime. | Ably Yes | Socket.IO Partial It is the duty of your application to link a Socket.IO connection to a user account. Read more |
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. | Ably Yes | Socket.IO |
Message interactions | Enables interaction with previously-sent messages, facilitating the implementation of features like message reactions and threads. | Ably Partial Message interactions are natively supported in ably-js. There is not currently any API support for retrieving messages and their interactions efficiently from the Realtime service (under development). Learn more | Socket.IO Partial You would need to build the message interaction functionality yourself on top of Socket.IO. Learn more |
Message history | Enables clients to catch up on missed messages when inactive, ensuring a user doesn’t miss any important messages. | Ably Yes | 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 |
Push notifications | Cross-platform push notifications make it possible to deliver important and timely messages to users even when they’re inactive. | Ably Yes Support for Android and iOS push notifications. Improved web-push for browsers currently in progress. | Socket.IO No Socket.IO not support Push notifications. You would need to build this capability yourself and/or use another library. Learn more |
Message delta compression | Minimizes bandwidth and can reduce latency, particularly in scenarios where continuous updates are sent. | Ably Yes Broadcast changes efficiently with our binary deltas, reducing bandwidth consumption by typically up to 95%. | Socket.IO No |
Programmatic management | Enables the automation of provisioning, management, and testing of service resources, simplifying integration with existing development workflows such as CI. | Ably Yes | 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 |
| 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. | Ably Yes | Socket.IO Yes Open Source framework that uses the MIT license. |
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. | Ably Ably offers a per-minute, consumption-based pricing model. This gives granular control over your costs, eliminating the need to pay for peak users or connections. The free and paid plans are:
| Socket.IO Free and open-source. |
| Integrations & interoperability | |||
SDKs | Supporting multiple languages and platforms offers greater flexibility when building cross-platform realtime apps. | Ably
| Socket.IO Client and Server APIs only.
|
Supported realtime protocols | Support for multiple protocols provides the flexibility to choose a protocol that best suits your project’s requirements. | Ably
| Socket.IO
|
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. | Ably
| 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 |
Streaming & queueing | Provides a dependable method to reroute messages from the service to third-party streams and queues for further processing. | Ably Egress:
Ingress:
The Database Connector is designed for any database in the SQL-family, but at the moment only supports Postgres. Please contact us if you want support in other databases. | Socket.IO No Socket.IO does not offer native queues and streaming. |
Observability services | Enables realtime monitoring and troubleshooting by offering insights into service behavior directly in your observability platform of choice. | Ably Yes | Socket.IO Yes The Socket.IO admin UI can be used to have an overview of the state of your Socket.IO deployment. |
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. | Ably
| Socket.IO No |
| Quality of Service | |||
Scalability | Scalability is vital as it ensures the service can handle increased data load or users without compromising performance. | Ably
| 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. |
Guaranteed message delivery | Ensures messages are never lost during transmission, even in the presence of network disruptions. | Ably Yes | 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. |
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. | Ably Yes | Socket.IO |
Exactly-once message delivery | Guarantees that each message is processed exactly once, preventing data inconsistencies that can arise from duplicate processing or missing messages. | Ably Yes | Socket.IO No At least once or at most once only. |
| 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. | Ably 99.999% | Socket.IO No It is a library, not a platform. |
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. | Ably Yes All Ably customer data runs across all our 7 geographically-distributed core routing datacenters by default. Ably's network of 385 edge acceleration points-of-presence is growing day by day. | Socket.IO No |
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. | Ably Yes | Socket.IO No |
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. | Ably Yes | Socket.IO No As Socket.IO is a library, the implementation of it dictates points of failure and congestion. |
Latency | Low latency is crucial for realtime apps as it ensures swift and efficient data transmissions, providing a smoother and more responsive user experience. | Ably <50ms round trip latency for the 99th percentile; <35ms latency once traffic arrives within AWS | Socket.IO Unknown |
| Security & compliance | |||
API key authentication | Simplifies the authentication code on trusted servers compared to requesting, managing, and refreshing tokens. | Ably Yes | Socket.IO No |
Token-based authentication | Provides a means to securely authenticate user devices against your user management system. | Ably Yes | Socket.IO No No native Token based auth. It is possible to use middlewares. |
Single Sign-On (SSO) authentication | SSO streamlines login processes, boosts security by minimizing password use, and meets compliance needs for secure data access management. | Ably Yes | Socket.IO No No native SSO. It is possible to use middlewares. |
Rules for permissions and operations | Provides control over which users can subscribe and publish to certain channels. | Ably Yes | Socket.IO No |
End-to-end encryption | Ensures that the data transmitted between the client and the API server remains confidential and secure while in transit. | Ably Yes Ably offers SSL/TLS encryption and 256-bit AES encryption using private keys. Message payloads can only be decrypted by other clients that share your secret key. Learn more about Ably's encryption | Socket.IO No |
Encryption at rest | Ensures data stored by the service is secure and compliant, while also mitigating the risks of a data breach. | Ably Yes | Socket.IO No |
Compliance | Compliance with regulations can impact your ability to meet legal obligations in your industry. | Ably
Ably also offers EU and US-only data storage. | Socket.IO None. |
Hear from companies gaining their realtime advantage with AblyThe core infrastructure for delivering live sports data to our customers is Ably. We sleep easier at night knowing it can be relied on for consistent low latency and message integrity at scale.”
Gary Williams
IT Infrastructure Team Lead
Ably immediately solved our issues around the user experience and scale. It supports our customers’ stringent expectations as well as future product development.”
Max Freiert
Product Group Lead
Ably copes easily with big loads. We don’t have to worry about stability, even when we get huge traffic spikes.”
Johan Bengtsson
CTO
Try Ably for free to discover the benefits for yourself
Ably has built reliable realtime infrastructure so you don’t have to. On our free plan you benefit from:
- 6M monthly messages
- 200 concurrent channels
- 200 concurrent connections
