PACKAGE · WEBSOCKET

ws

Simple to use, blazing fast and thoroughly tested websocket client and server for Node.js

WEEKLY DOWNLOADS 111.0M
STARS 22.8K
FORKS 2.6K
OPEN ISSUES 5
GZIP SIZE 511 B
UNPACKED SIZE 151.1 kB
DEPENDENCIES 1
LAST UPDATED 5mo ago
DOWNLOAD TRENDS

ws downloads — last 12 months

Download trends for ws1 download series from Jun 2025 to May 2026. Use left and right arrow keys to inspect monthly values.0223.1M446.2M669.3M892.5MJun 2025SepDecMarMay 2026
ws
ABOUT WS

The 'ws' package provides a comprehensive and highly performant implementation of the WebSocket protocol (RFC 6455) for Node.js, addressing the need for real-time, bidirectional communication between clients and servers. It simplifies the integration of live data feeds, chat applications, and other interactive features by abstracting away the complexities of WebSocket connection management, framing, and negotiation.

The core design philosophy behind 'ws' emphasizes speed, robustness, and ease of use, making it suitable for a broad range of developers from those building rapid prototypes to those deploying high-traffic real-time services. Its architecture is built for performance, leveraging native Node.js capabilities where possible to ensure low latency and high throughput for connected clients.

Key API patterns include straightforward event-driven interfaces for managing connections, such as 'on("connection")' for servers to accept incoming clients, and 'on("message")', 'on("close")', and 'on("error")' for both server and client instances to handle communication events. The package supports various WebSocket options for customization, including per-message deflate compression.

'ws' integrates seamlessly into standard Node.js applications and can be easily integrated with popular web frameworks like Express or Koa by mounting the WebSocket server alongside an HTTP server. Its straightforward API means developers can quickly set up WebSocket endpoints without extensive boilerplate code, fitting naturally into existing request-response or streaming architectures.

With over 223.7 million weekly downloads and a legacy of thorough testing, 'ws' represents a mature and battle-tested solution for WebSocket communication. Its unpacked size of 151.1 kB and gzipped bundle size of only 511 B indicate a highly optimized footprint, crucial for performance-sensitive applications.

While 'ws' excels at standard WebSocket communication, developers should be aware that it primarily focuses on the core protocol. More complex features like automatic reconnection, message queuing, or advanced state synchronization might require additional logic or complementary libraries built on top of its foundational capabilities.

WHEN TO USE
  • When implementing real-time features such as live chat, collaborative editing, or multiplayer game state updates.
  • When building custom backend services that require a direct, persistent connection with clients for instant data transfer.
  • When integrating real-time notifications or dashboard updates into an existing Node.js web application.
  • When needing to handle high volumes of concurrent WebSocket connections efficiently.
  • When your application requires adherence to the WebSocket protocol (RFC 6455) with a focus on performance and reliability.
WHEN NOT TO USE
  • If your requirement is solely for simple request-response HTTP communication, a standard HTTP server library is more appropriate.
  • If you only need basic client-side messaging and can achieve this through built-in browser WebSocket APIs without a Node.js backend.
  • If your application involves complex pub/sub patterns or message broadcasting logic that is better handled by a dedicated message broker solution.
  • If you require a higher-level abstraction for managing complex state synchronization across many clients, consider libraries that specifically address these patterns.
  • If your primary need is for server-sent events (SSE), which uses a different protocol designed for one-way server-to-client streaming.

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COMPARISONS 5
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