Node.js Buffer.concat() Method Last Updated : 11 Apr, 2023 Comments Improve Suggest changes Like Article Like Report The Buffer.concat() method is used to concat all buffer objects in a given array into one buffer object. The return value of this method is also a buffer. If the length of the buffer is not provided then it is calculated from the Buffer instances in the list. Syntax: Buffer.concat( list, length ) Parameters: This method accepts two parameters as mentioned above and described below: list: Contains the list of buffers to concat.length: It defines the length of the concatenated buffer. This parameter is optional. Example 1: In this example, we will see the use of Buffer.concat() method javascript // Returns a new buffer with the // copy of the passed string const buf1 = Buffer.from("Geeks"); // Returns another buffer with // copy of the passed string const buf2 = Buffer.from("for"); const buf3 = Buffer.from("Geeks"); // Creates an array of buffers const list = [buf1, buf2, buf3]; // Concatenates all buffer objects into one buffer const newbuff = Buffer.concat(list); console.log("The concatenated buffer:"); // Displays the concatenated buffer console.log(newbuff); Output: The concatenated buffer: <Buffer 47 65 65 6b 73 66 6f 72 47 65 65 6b 73> Example 2: In this example, we will see the use of the Buffer.concat() method javascript // Returns a new buffer with the // copy of the passed string const buf1 = Buffer.from("Good"); // Returns another buffer with // copy of the passed string const buf2 = Buffer.from("morning"); const buf3 = Buffer.from("everyone"); // Creates an array of buffers const list = [buf1, buf2, buf3]; // Concatenates all buffer objects // into one buffer const newbuff = Buffer.concat(list); console.log("The concatenated buffer:"); // Displays the concatenated buffer console.log(newbuff); Output: The concatenated buffer: <Buffer 47 6f 6f 64 6d 6f 72 6e 69 6e 67 65 76 65 72 79 6f 6e 65> Note: The above program will compile and run by using the node index.js command. Reference: https://nodejs.org/dist/latest-v13.x/docs/api/buffer.html#buffer_class_method_buffer_concat_list_totallength Create Quiz Comment A ankit0812 Follow 0 Improve A ankit0812 Follow 0 Improve Article Tags : Web Technologies Node.js Node.js-Buffer-module Explore Introduction & Installation NodeJS Introduction3 min readNode.js Roadmap: A Complete Guide6 min readHow to Install Node.js on Linux6 min readHow to Install Node.js on Windows5 min readHow to Install NodeJS on MacOS6 min readNode.js vs Browser - Top Differences That Every Developer Should Know6 min readNodeJS REPL (READ, EVAL, PRINT, LOOP)4 min readExplain V8 engine in Node.js7 min readNode.js Web Application Architecture3 min readNodeJS Event Loop5 min readNode.js Modules , Buffer & StreamsNodeJS Modules5 min readWhat are Buffers in Node.js ?4 min readNode.js Streams4 min readNode.js Asynchronous ProgrammingAsync Await in Node.js3 min readPromises in NodeJS7 min readHow to Handle Errors in Node.js ?4 min readException Handling in Node.js3 min readNode.js NPMNodeJS NPM6 min readSteps to Create and Publish NPM packages7 min readIntroduction to NPM scripts2 min readNode.js package.json4 min readWhat is package-lock.json ?3 min readNode.js Deployments & CommunicationNode Debugging2 min readHow to Perform Testing in Node.js ?2 min readUnit Testing of Node.js Application5 min readNODE_ENV Variables and How to Use Them ?2 min readDifference Between Development and Production in Node.js3 min readBest Security Practices in Node.js4 min readDeploying Node.js Applications5 min readHow to Build a Microservices Architecture with NodeJS3 min readNode.js with WebAssembly3 min readResources & ToolsNode.js Web Server6 min readNode Exercises, Practice Questions and Solutions4 min readNode.js Projects9 min readNodeJS Interview Questions and Answers15+ min read Like