The Buffer class is a subclass of JavaScript's <Uint8Array> class and extends it with methods that cover additional use cases.

It is an array of bytes, often referred to in other languages as a "byte array". You cannot directly manipulate the contents of an ArrayBuffer; instead, you create one of the typed array objects or a DataView object which represents the buffer in a specific format, and use that to read and write the contents of the buffer.

July 10, 2025 - The buffer property is an accessor property whose set accessor function is undefined, meaning that you can only read this property. The value is established when the TypedArray is constructed and cannot be changed.

Buffers are similar to arrays of integers but are fixed-length and correspond to raw memory allocations outside the V8 JavaScript engine.

The Buffer constructor returns instances of Uint8Array that have their prototype changed to Buffer.prototype. Furthermore, Buffer is a subclass of Uint8Array, so the returned instances will have all the node Buffer methods and the Uint8Array methods.

July 10, 2025 - const buffer = new ArrayBuffer(8); const dataview = new DataView(buffer); dataview.buffer; // ArrayBuffer { byteLength: 8 }

October 24, 2023 - The Buffer type has been the cornerstone for binary data handling in Node.js since the beginning. However, these days we have Uint8Array, which is a native JavaScript type and works cross-platform. While Buffer is an instance of Uint8Array, it introduces numerous methods that are not available in other JavaScript environments.

February 8, 2023 - So, what exactly is a Buffer? Simply put, a Buffer is a way to store and manipulate binary data in Node.js. Binary data refers to data that consists of binary values, as opposed to text data, which consists of characters and symbols.

January 5, 2024 - Uint8Array is defined in all modern JavaScript runtimes, Buffer is not.

July 22, 2025 - Buffers in Node.js are as close to the metal as you can get in JavaScript, raw binary data, fast, easy to transport and transform.

May 1, 2020 - A buffer is a space in memory (typically RAM) that stores binary data. In Node.js, we can access these spaces of memory with the built-in Buffer class. Buffers store a sequence of integers, similar to an array in JavaScript.

July 26, 2026 - This API — a fairly low-level one — is Buffer. ... Ever since the advent of ES6, JavaScript has gotten native provision of array buffers and typed arrays (to lay out views over those buffers).

It stores raw data similar to an array of integers but corresponds to a raw memory allocation outside the V8 heap. The Buffer class in Node.js is a subclass of JavaScript's Uint8Array class.

March 27, 2024 - Within Node.js, a buffer is a global object that provides a way to work with binary data directly. Unlike arrays that you might be used to in other programming languages, buffers in Node.js deal with raw memory allocation outside the V8 JavaScript ...

June 4, 2024 - Walk through the basics of the Node.js buffer module and learn how to use Node.js buffer methods in your own application.

April 15, 2026 - Buffer in Node.js is a built-in object used to handle and manipulate raw binary data, especially when working with streams, files, or network operations.

July 4, 2024 - A Buffer in Node.js is a temporary storage area in memory used to hold raw binary data. It is a fixed-length sequence of bytes, similar to an array of integers, but corresponds to a raw memory allocation outside the V8 JavaScript engine.

December 14, 2023 - Within Node.js, a buffer is a global object that provides a way to work with binary data directly. Unlike arrays that you might be used to in other programming languages, buffers in Node.js deal with raw memory allocation outside the V8 JavaScript ...

Node.js buffers are objects that store arbitary binary data.

August 16, 2024 - If you try to write code using Buffer it will break in any other non-Node.js platform. The reason is simple, it is Node.js specific API. Instead, you can use typed arrays like Uint8Array or Int8Array. They are part of ECMAScript standard, and all big platforms that are running JavaScript support them.