Real-time chat APIs

For adding real-time chat to your app, I’d start by comparing Stream Chat, Sendbird, and PubNub. They all support real-time messaging, but they solve slightly different problems.

The best choice depends on whether you want a complete, ready-to-use chat experience with UI components, a highly customizable messaging platform, or lower-level real-time infrastructure that gives you more control.

My default recommendation is Stream Chat if you want to ship a polished chat feature quickly without building messaging infrastructure yourself.

Best chat-as-a-service APIs compared

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1. Stream Chat

(Best overall)

Best for social apps, marketplaces, communities, and products that need a polished messaging experience.

• Rich chat SDKs and customizable UI components
• Message history, reactions, threads, typing indicators, and moderation features
• Good choice when you want to avoid building the chat stack yourself

Pricing: free development tier; paid production plans start at a higher usage tier.

Website · Documentation ·Pricing

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2. Sendbird

Best for enterprise messaging

A strong option for customer-facing apps that need mature messaging features, moderation, and optional voice or video capabilities.

• Web and mobile SDKs with UI kits
• Messaging tools for larger communities and business use cases
• Enterprise-oriented plans and support

Pricing: free trial; published Starter pricing begins at $349/month with annual billing for 5,000 monthly active users.

Website · Documentation ·Pricing

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3. TalkJS

Best for fast integration

Especially attractive for web apps that need one-to-one messaging, group chats, and a customizable ready-made interface.

• Hosted messaging backend and prebuilt UI
• Less chat UI work for your engineering team
• Straightforward option for marketplaces and customer-user conversations

Pricing: paid plans are primarily based on monthly active users; verify current limits and features.

Website · Documentation ·Pricing

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4. Ably

Best for custom real-time systems

Choose Ably if you want real-time infrastructure that can power chat alongside live updates, collaboration, and other event-driven features.

• Pub/sub messaging and connection recovery
• Flexible building blocks for custom experiences
• More application-level engineering than a turnkey chat SDK

Website · Documentation ·Pricing

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5. PubNub

Best for broader real-time features

Worth considering if your app needs chat plus live presence, event streams, location updates, or other real-time interactions.

• Real-time publish/subscribe infrastructure
• Flexible client SDKs
• You may need to implement more of the chat experience yourself

Website · Documentation ·Pricing

These recommendations reflect the vendors' product positioning and published comparisons. For a useful independent starting point, see the 2026 chat API comparison and the September 2026 pricing comparison. Pricing and quotas differ substantially, so compare the actual plan limits rather than just the headline monthly price.frontdeskreview.com+3

Which one would I actually choose?

One important consideration: pricing can change significantly with monthly active users (MAU), concurrent connections, message retention, and overages. For example, Sendbird's published Starter plan is $349/month with annual billing, while Stream's Start plan has been listed at $399/month with annual billing for 10,000 MAU. Check the linked pricing pages for current terms.sendbird.com+1

Let me narrow it down for your app

What are you building, and what tech stack are you using? That will help me recommend the best API for your particular use case, including cost and integration effort.

If you want a managed API rather than building WebSockets/chat infrastructure yourself, I’d shortlist Stream Chat, Sendbird, Ably, and PubNub. Firebase/Firestore and Supabase are also good, but they’re more general backend/realtime platforms than turnkey chat products.

My shortlist

🥇 My default recommendation: Stream

For a typical SaaS/product where you want “add chat without becoming a chat infrastructure company,” I'd start with Stream.

Its Chat API handles channels, messages, threads, reactions and read state, while its SDKs include offline support and prebuilt UI components. It has client SDKs for React, iOS, Android, React Native, Flutter, Unity, etc., plus backend SDKs.getstream.io

Its current published pricing starts with a free tier at 1,000 MAU/100 concurrent connections; the 10K-MAU Start tier is listed at $399/month annually or $499 monthly.getstream.io

Choose Stream if: chat is a significant product feature and you want the shortest path to a polished UX.

Stream Chat

🥈 Sendbird — strongest enterprise alternative

Sendbird is particularly compelling for customer support, marketplaces, social apps, and enterprise applications. Its SDK/UI approach is similar to Stream, with React, React Native, Flutter, iOS and Android UI components plus a server-side Platform API.sendbird.com

Its current pricing shows a Starter 5K plan at $349/month annually ($399 monthly) and Pro 5K at $499/month annually ($599 monthly), with enterprise options and overages. sendbird.com It also advertises SOC 2, ISO 27001, GDPR and HIPAA/BAA options.sendbird.com

Choose Sendbird if: enterprise requirements, compliance, support, and a full-featured chat product matter more than minimizing cost.

Sendbird Chat

🥉 Ably — best if realtime infrastructure is the bigger problem

Ably is slightly different. Rather than just giving you a chat database/API, it gives you a powerful realtime messaging infrastructure with a dedicated Chat SDK.

It supports rooms, message history, presence, typing indicators, reactions, editing/deletion and moderation, with SDKs for JavaScript/React, Kotlin/Android and Swift.ably.com

It's especially interesting for livestream chat, very high concurrency, multiplayer-ish experiences, or applications where realtime events extend beyond chat. Ably explicitly positions its Chat SDK for experiences involving hundreds of thousands or millions of users.getstream.io+1

Choose Ably if: you expect unusual realtime scale or want one realtime platform that can eventually power things besides chat.

Ably Chat

PubNub — another strong high-scale choice

PubNub has been doing realtime messaging for a long time and its Chat SDK provides typing indicators, threaded messages, reactions, read receipts, presence and moderation. It supports a very broad range of platforms with 50+ SDKs.www.pubnub.com

Its current pricing can be based on MAUs, with a free tier of 200 MAU or 1M transactions and a Starter plan listed at $98/month for 1,000 MAU.www.pubnub.com

Choose PubNub if: realtime messaging is central to your architecture and you want a mature global pub/sub layer rather than just a chat database.

PubNub Chat

What about Supabase/Firebase?

These are attractive when you already use their databases.

Supabase Realtime charges based on messages and peak connections; its current Pro/Team allowance is 5M realtime messages and 500 peak connections, with overages of $2.50/M messages and $10/1,000 peak connections.supabase.com

Firebase Firestore can implement chat very effectively, but you're building more of the chat product yourself. Realtime listeners are billed as document reads, alongside writes, deletes, storage and bandwidth.firebase.google.com

So I'd pick them when your requirement is more like “I need realtime data synchronization” rather than “I need a complete chat backend.”

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My decision tree

If I were choosing today:

• Slack/Discord-style messaging → Stream
• Customer support / enterprise chat → Sendbird
• Livestream or enormous realtime audiences → Ably
• Realtime-heavy product with many event types → PubNub
• Already on Postgres/Supabase → Supabase Realtime
• Already deeply invested in Firebase → Firestore

One important architectural point: even with these services, keep your own user/account/authorization system as the source of truth. Your backend should mint the provider's user tokens and control which users can access which conversations. Stream, for example, explicitly requires production applications to sign user tokens server-side.getstream.io

If you tell me roughly (1) expected MAUs, (2) peak concurrent users, (3) web/mobile/both, (4) 1:1 vs group chat, and (5) whether you need attachments, moderation, or end-to-end encryption, I can narrow this to the best 2 options and estimate the monthly cost.

When choosing a managed WebSocket infrastructure for a real-time chat feature, there is no single "best" option for every team , but a few industry leaders stand out depending on your scale, budget, and architectural preferences.

The top-tier managed services and how they fit a chat application include:

• Ably — Best overall for enterprise-grade reliability and strict guarantees. Ably provides guaranteed message delivery, integrated token authentication, historical message recovery (crucial for users reconnecting after dropping offline), and built-in presence awareness (who is online/typing). It is heavily relied upon for mission-critical chat infrastructure because it eliminates edge-case message loss. You can explore their platform on Ably Realtime.[pkgpulse.com](https://www.pkgpulse.com/guides/best-realtime-libraries-2026)
• Pusher (Channels) — Best for developer ergonomics and fast setup. Pusher is one of the oldest and most straightforward hosted pub/sub WebSocket layers. It has fantastic documentation, a shallow learning curve, and works wonderfully for standard chat rooms and notifications. However, it can become expensive at massive scale compared to managing your own infrastructure or using usage-optimized alternatives. Learn more at Pusher.[pkgpulse.com](https://www.pkgpulse.com/guides/best-realtime-libraries-2026)[[2](https://ably.com/compare/centrifugo-vs-pusher)](https://ably.com/compare/centrifugo-vs-pusher)
• PubNub — Best for global footprint and IoT-adjacent features. PubNub offers a massive global edge network and heavy-duty features, though its architectural roots are partially HTTP-based rather than strictly native WebSocket streams, which can introduce minor throughput/latency ceilings for intensive chat apps. Check them out via PubNub.[pkgpulse.com](https://websocket.org/comparisons/managed-services/)
• Centrifugo (Managed/PRO) — Best cost-to-performance ratio if you want self-hosted control or hybrid flexibility. While Centrifugo is fundamentally an open-source, self-hosted Go server, they offer professional/managed tiers. It is exceptionally fast and lightweight, handling millions of connections on minimal hardware if you prefer not to pay per-message or per-connection fees to a massive SaaS provider.[pkgpulse.com](https://ably.com/compare/centrifugo-vs-pusher)[[2](https://ably.com/compare/centrifugo-vs-pusher)](https://ably.com/compare/centrifugo-vs-socketio)
• Socket.IO (Self-Hosted / Managed via third-party) — The community standard for custom control. Socket.IO itself is a library, not a managed cloud service. To make it a managed infrastructure for chat, you have to run it behind a Redis adapter on your own Kubernetes/ECS cluster. Great if you want zero vendor lock-in, but you inherit the scaling and debugging overhead.[pkgpulse.com](https://www.pkgpulse.com/guides/best-realtime-libraries-2026)

To help narrow down which infrastructure fits your exact stack, could you share:

• What is your expected concurrent connection scale (e.g., hundreds vs. millions)?
• Are you deployed on serverless (Vercel, Cloudflare Workers) or traditional servers (Node.js, Go, Kubernetes)?
• Do you need built-in message history/persistence , or are you storing chat logs in your own database (like PostgreSQL/MongoDB)?

For a real-time chat feature, choosing a managed WebSocket service saves you from wrestling with horizontal scaling, Redis pub/sub clusters, load balancers, and painful connection state drops on mobile.[pkgpulse.com](https://www.pkgpulse.com/guides/best-realtime-libraries-2026)

The top managed WebSocket options tailored for chat break down as follows:

• Ably Realtime — The Gold Standard for Chat Reliability
  • Best for: Production-grade chat requiring strict data integrity.
  • Why it shines: Ably is built with protocol-level message ordering and guaranteed, exactly-once delivery. If a user goes through a tunnel and drops connection, Ably’s built-in connection state recovery automatically replays missed messages seamlessly. It also features robust built-in presence (who's online/typing) and message history.
  • Trade-off: More expensive at scale than raw infrastructure, though it has a generous free tier.[pkgpulse.com](https://websocket.org/comparisons/managed-services/)[[2](https://websocket.org/comparisons/managed-services)](https://websocket.org/comparisons/managed-services/)[[3](https://www.buildmvpfast.com/compare/pusher-vs-ably)](https://www.pkgpulse.com/guides/best-realtime-libraries-2026)[[4](https://stackoverflow.com/questions/62501036/how-to-choose-realtime-push-notifications-api)](https://www.pkgpulse.com/guides/best-realtime-libraries-2026)
• Pusher Channels — The Fastest to Integrate
  • Best for: MVPs, smaller apps, or straightforward chat features where time-to-market is everything.
  • Why it shines: Pusher is battle-tested, incredibly easy to pick up, and has some of the cleanest documentation in the industry. It supports private/authenticated channels and basic presence channels out of the box.
  • Trade-off: Lacks advanced enterprise features like guaranteed message ordering or native history storage. If a client drops offline, catching up on missed messages requires rolling your own database fetching layer.[pkgpulse.com](https://www.buildmvpfast.com/compare/pusher-vs-ably)[[2](https://websocket.org/comparisons/managed-services)](https://websocket.org/comparisons/managed-services/)
• PubNub — The Heavy-Duty Global Data Streamer
  • Best for: Complex chat ecosystems with massive data distribution needs or multi-region routing.
  • Why it shines: Massive scalability, powerful access control, and native persistence/history features. (Note: PubNub relies heavily on a robust HTTP-based data stream network under the hood rather than pure raw WebSockets, but exposes real-time behaviors effectively).
  • Trade-off: The API paradigm can feel a bit more verbose and structurally heavy compared to Pusher or Ably.[pkgpulse.com](https://stackoverflow.com/questions/62501036/how-to-choose-realtime-push-notifications-api)[[2](https://websocket.org/comparisons/managed-services)](https://websocket.org/comparisons/managed-services/)
• AWS API Gateway (WebSockets) — The DIY Cloud-Native Route
  • Best for: Teams deeply embedded in the AWS ecosystem who want a serverless architecture connected to DynamoDB/Lambda.
  • Why it shines: Keeps you within your cloud provider perimeter; pay-per-connection model with no idle server costs.
  • Trade-off: It is not a plug-and-play chat backend. You have to manage connection IDs manually in a database (like DynamoDB), write the routing logic yourself via Lambda, and handle reconnections/presence entirely from scratch.[pkgpulse.com](https://www.buildmvpfast.com/compare/pusher-vs-ably)

Quick Recommendation

• Go with Pusher if you are building an MVP or simple team chat and want it working by tonight.
• Go with Ably if you are building a serious product where dropped messages, out-of-order text bubbles, or flaky mobile reconnections will ruin the user experience.[pkgpulse.com](https://websocket.org/comparisons/managed-services/)[[2](https://websocket.org/comparisons/managed-services)](https://www.buildmvpfast.com/compare/pusher-vs-ably)[[3](https://www.buildmvpfast.com/compare/pusher-vs-ably)](https://websocket.org/comparisons/managed-services/)[[4]()]()

To help narrow this down, tell me:

• Expected peak concurrent connections?
• Are you deploying on serverless (e.g., Vercel, Cloudflare) or traditional servers?
• Do you need out-of-the-box message history persistence and typing indicators/presence?