Ably vs CometChat

Discover how CometChat compares to Ably, and understand which is right for your use case, based on dimensions such as scalability, pricing, security, and their chat features.

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 CometChat?

CometChat is a messaging platform designed for integration into various applications, offering text, voice, and video chat capabilities. It supports extensive customization through SDKs and UI kits.

Compare Ably and CometChat

Let’s compare Ably and CometChat, looking at key elements of their offering such as their scalability, pricing, security and chat feature set.

Disclaimer: This comparison was created based on documentation and resources freely available online about Ably and CometChat. The content was last updated on 30 Apr 2025 for Ably and on 1 May 2025 for CometChat. 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 If you do find anything incorrect or out of date, then please let us know.

Hear from companies gaining their realtime advantage with Ably

“

The 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

Read case study

“

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

Read case study

“

Ably copes easily with big loads. We don’t have to worry about stability, even when we get huge traffic spikes.”

Johan Bengtsson

CTO

Read case study

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

Get started for free Read our docs

	Ably	CometChat	Why this matters
Scalability
Concurrent connections	Number of users that can be supported in a single chat.	Ably Yes Unlimited - no additional charge for concurrency. See pricing for details	CometChat Up 100k concurrent connections can be supported. The use of certain features, such as delivery receipts, read receipts, and typing indicators, may impact these limits. For example, groups with all features enabled can accommodate up to 300 members.	Number of users that can be supported in a single chat.
Connections	Number of connections that can be handled across the platform.	Ably Yes Unlimited. See pricing for details	CometChat Up to 500k.	Number of connections that can be handled across the platform.
Channels / rooms	Number of channels or rooms that can be handled across the platform.	Ably Yes Unlimited. See pricing for details	CometChat Unlimited.	Number of channels or rooms that can be handled across the platform.
Messages	Number of messages that can be handled across the platform.	Ably Unlimited. See pricing for details	CometChat Unlimited.	Number of messages that can be handled across the platform.
Message throughput	Number of messsages that can be published per second.	Ably From: 2.5k messages/second in our Standard plan 10k messages/second in Pro Unlimited for Enterprise plans See pricing for details	CometChat Up to 333 messages per second. API calls for standard operations are rate limited to 20000 requests per min.	Number of messsages that can be published per second.
Data integrity
Guaranteed message delivery	Ensures messages are never lost during transmission, even in the presence of network disruptions.	Ably Yes	CometChat No	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.	Ably Yes	CometChat No	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.	Ably Yes	CometChat No	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.	Ably 99.999%.	CometChat 99.99% uptime guarantee. Read more	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.	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.	CometChat Yes Read more	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.	Ably Yes	CometChat 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.	Ably Yes	CometChat No	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.	Ably <50ms round trip latency for the 99th percentile <35ms latency once traffic arrives within AWS	CometChat Under optimal test conditions, CometChat has a one-way latency of less than 50 ms response time. It is not mentioned what its roundtrip latency is. Read more	Low latency is crucial for realtime apps as it ensures swift and efficient data transmissions, providing a smoother and more responsive user experience.
Server-side batching	Reduces the overall message count, lowers costs, and mitigates the risk of hitting rate limits during high-throughput scenarios.	Ably Yes	CometChat No	Reduces the overall message count, lowers costs, and mitigates the risk of hitting rate limits during high-throughput scenarios.
Connection state recovery	Automatically re-establish failed connections and replay missed messages.	Ably Yes	CometChat Yes CometChat supports connection state recovery, monitoring realtime connection status to its WebSocket servers. If disconnected, the SDK auto-reconnects, indicating "connecting" and "connected" states. Read more	Automatically re-establish failed connections and replay missed messages.
Ecosystem support
Supported realtime protocols	Support for multiple protocols provides the flexibility to choose a protocol that best suits your project’s requirements.	Ably WebSockets MQTT Server-Sent Events (SSE) Fallback to Comet (XHR) and Long Polling for older browsers	CometChat WebSocket.	Support for multiple protocols provides the flexibility to choose a protocol that best suits your project’s requirements.
Supported languages	Supporting multiple languages and platforms offers greater flexibility when building cross-platform realtime apps.	Ably JavaScript React Kotlin Swift	CometChat CometChat supports several programming languages for effective integration with CometChat's SDKs and APIs: React Vue Swift (for iOS) Kotlin (for Android) PHP Angular React Native Flutter CometChat SDK page	Supporting multiple languages and platforms offers greater flexibility when building cross-platform realtime apps.
Chat room types
Multi-type chat support (group, DM, supergroups)	Enables chat experiences to be tailored to various user needs, from one-on-one to large, scalable group discussions.	Ably 1:1 1:many many:many	CometChat Group chat channels Supergroup channels Private and public chat groups Direct message messaging	Enables chat experiences to be tailored to various user needs, from one-on-one to large, scalable group discussions.
Chat room management
Presence	Maintaining a view of which users are connected, and their associated metadata, enables their online status to be updated in realtime.	Ably Yes	CometChat Yes CometChat supports user presence out-of-the-box through CometChat SDKs and its UI kits. The SDKs include options for subscribing to presence updates to all users, specific roles, or friends.	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.	Ably Yes	CometChat No	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.
Typing indicators	Show when others are typing in a chat room, enhancing realtime communication flow.	Ably Yes Ably Chat provides typing indicators to show when users are composing messages.	CometChat Yes	Show when others are typing in a chat room, enhancing realtime communication flow.
Room reactions	Customize the chat environment with reactions and other shared room states.	Ably Yes Ably Chat supports room-level reactions with a variety of emojis. Ephemeral reactions are not counted or aggregated.	CometChat No	Customize the chat environment with reactions and other shared room states.
Chat message attributes
Message edits and deletes	Allow users to modify or remove messages.	Ably Yes Ably Chat supports soft deletion of messages and message edits.	CometChat Yes	Allow users to modify or remove messages.
Message reactions & emoticons	Boost engagement by enabling users to quickly express emotions or feedback on messages.	Ably Yes Ably Chat supports reactions at the room level and message level.	CometChat Yes	Boost engagement by enabling users to quickly express emotions or feedback on messages.
Rich text support	Enhance messages with rich text formatting in chat.	Ably Yes	CometChat Yes	Enhance messages with rich text formatting in chat.
Media attachments	Support for sharing images, videos, and files in chat.	Ably Partial Links are supported.	CometChat Yes CometChat in-app messaging allows users to send and receive various documents and multimedia files through its SDKs and UI kits. Read more	Support for sharing images, videos, and files in chat.
Chat application and user state
In-app notifications	Notify users of important events from other chat rooms without them leaving the current chat, keeping them engaged and informed.	Ably Yes In-app notifications supported via Ably Pub/Sub.	CometChat Yes CometChat supports in-app notifications through CometChat's push notification service.	Notify users of important events from other chat rooms without them leaving the current chat, keeping them engaged and informed.
Role-based permissions	Control user roles and permissions to ensure proper access and moderation.	Ably No Ably Chat doesn't current support role-based permissions, but will soon.	CometChat Yes	Control user roles and permissions to ensure proper access and moderation.
UI kit	Customizable UI elements for a seamless chat integration.	Ably No Ably Chat doesn't currently offer a UI kit.	CometChat Yes CometChat supports UI kits for: Android iOS React Flutter Vue Angular	Customizable UI elements for a seamless chat integration.
Storage and history
Synchronous - automated moderation	Detect and manage harmful content automatically, before the message is broadcast to participants.	Ably Yes Ably Chat supports synchronous moderation using Hive AI. You can also integrate with a third-party moderation provider.	CometChat Yes	Detect and manage harmful content automatically, before the message is broadcast to participants.