Why our customers choose Ably over Pusher

Ably is an enterprise-grade serverless WebSockets platform for pub/sub messaging at the edge. Our customers trust in Ably to power scalable and realtime online user experiences that will work anywhere in the world, without fail.

We provide an elastic, hyper-reliable global infrastructure that also comes with the flexible building blocks needed for creating rich user experiences. Everything is offered via consistent and intuitive APIs.

Focus on building realtime apps that delight customers. We’ll handle the rest.

Ably is a serverless edge messaging platform designed to stream realtime messages at extreme scale to web, mobile, and IoT devices, over a fault-tolerant, autoscaling global edge network. We deliver 750+ billion messages to more than 300 million end-users each month.

As a managed solution, Ably enables you to:

  • Easily build high-performance realtime functionality that delights your users.

  • Reduce engineering and DevOps efforts - there's no complex realtime infrastructure for you to provision and maintain.

Start with a free account Read our docs

Copy link to clipboard

Key Ably advantages vs Pusher



QoS, message delivery guarantee & connection state recovery

Ably's round trip latencies, measured as the time taken to publish a message on one connection and receive a message on another connection, dependably range from 5ms to 200ms, with a median global latency of 65ms.

If a message is published whilst a client is briefly disconnected (such as going through a tunnel or changing networks), then the message published over Pusher will never arrive to that client.

Reliable message ordering

Ably ensures that messages are delivered to persistently connected subscribers in the order they were published on each channel using the First-in-First-Out (FIFO) pattern.

Pusher does not support reliable message ordering.

Low latencies globally

Ably’s round trip latencies, measured as the time taken to publish a message on one connection and receive a message on another connection, dependably range from 30ms to 100ms globally.

Pusher’s average global latencies range between 90ms and 200ms. As Pusher apps exist in one only region, message latencies increase for clients the further they are from the chosen datacenter.

Global datacenters

Ably has 16 datacenters spread across four continents so your users are never far from the Ably network. We ensure complete availability by routing to the next-closest alternative datacenter when necessary.

One per app. Pusher requires you to choose a single datacenter for an app to reside in. All realtime traffic must therefore be routed through a single datacenter, regardless of a user’s location. This has implications for performance, reliability, and availability.

No single point of failure

Ably’s Data Stream Network is a distributed system designed with no single point of failure. All customers benefit from running their apps in all of our datacenters providing resilience, reliability, and global low latencies.

Pusher apps are located in a single datacenter rather than distributed across multiple datacenters. If that datacenter goes offline then all apps hosted there are affected.

Message history (persisted data)

Ably’s message history feature provides a means for clients or servers to retrieve messages that were previously published on a channel.

Pusher does not support message history.

Robust features set to power delightful realtime experiences


Publish messages to millions of subscribers over Ably channels - named units of distribution that offer a way to implement Pub/Sub messaging and realtime data delivery.


Ably supports WebSockets, SSE, and MQTT, so you can choose the right protocol for your use case. We also support the Pusher and PubNub protocols, making the migration to Ably quick and simple.


No message is ever lost, delivered multiple times, or out of order, even if unreliable networks and brief disconnections are involved.


Subscribe to events when devices or users enter, leave, or update their state on channels. Essential for use cases like chat, multiplayer games, or collaboration tools.


Reduce the bandwidth needed to distribute messages to consumers by sending only the changes from the previous message instead of the entire payload.


Send push notifications over Ably channels, or deliver them directly to Android and iOS users with FCM and APNs.

Simple and powerful client library SDKs

All official Ably client library SDKs offer a consistent yet idiomatic API across every language. Regardless of your development environment or preferred language, Ably keeps things simple for you by providing consistency and predictability. You can quickly integrate our SDKs into your tech stack with a few lines of code, and start building realtime features in minutes. 

Migrate to Ably

Ably is the only cloud vendor that supports the Pusher protocol. It’s simple to migrate to Ably, or use Ably as a failover for Pusher in hours instead of months.