This code will show the data buffer as a hex string:

buff.toString('hex');
Answer from Seryh on Stack Overflow
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Stack Overflow
stackoverflow.com › questions › 18879880 › how-to-display-nodejs-raw-buffer-data-as-hex-string
node.js - How to display nodejs raw Buffer data as Hex string - Stack Overflow
Top answer
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297

This code will show the data buffer as a hex string:

buff.toString('hex');
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3

Top answer is the simplest way to do it.

An alternative method:

data = Buffer.from([0x62, 0x75, 0x66, 0x66, 0x65, 0x72]);

Array.prototype.map.call(new Uint8Array(data),
               x => ('00' + x.toString(16)).slice(-2))
        .join('').match(/[a-fA-F0-9]{2}/g).reverse().join('');
node.js - What encodings does Buffer.toString() support?
node.js - Access Buffer - Javascript
node.js - Send and receive hex codes over nodejs socket
converting string into hex in js
node.js - How to convert String into Hex nodejs
More results from stackoverflow.com
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Bun
bun.com › modules › node:buffer › buffer › tohex
Buffer.toHex method | Node.js buffer module | Bun
March 21, 2026 - Convert the Uint8Array to a hex encoded string ·
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Stack Overflow
stackoverflow.com › questions › 59843140 › converting-a-buffer-to-a-hex-string
node.js - Converting a buffer to a hex string - Stack Overflow
Top answer
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3

This works for me... is your object actually an Node.js buffer?

Buffer.from([255,254,0,1]).toString("hex") // ffee0001
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Medium
medium.com › deno-the-complete-reference › deno-nuggets-buffer-to-hex-one-liner-701e4ce074a2
Deno nuggets: Buffer to hex one-liner | Tech Tonic
April 6, 2023 - const buf = new TextEncoder().encode("Hello from JS ArrayBuffer!"); const hex = Array.from(buf).map((b) => b.toString(16).padStart(2, "0")).join(""); console.log("// -- BUFFER:\n\n", buf, "\n\n// -- HEX:\n\n", hex); ... // -- BUFFER:Uint8Array(26) [ 72, 101, 108, 108, 111, 32, 102, 114, 111, 109, 32, 74, 83, 32, 65, 114, 114, 97, 121, 66, 117, 102, 102, 101, 114, 33 ]// -- HEX:48656c6c6f2066726f6d204a5320417272617942756666657221 ... Articles on popular things like Node.js, Deno, Bun, etc.
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GitHub
github.com › nodejs › node › issues › 24491
Buffer.from for the hex string · Issue #24491 · nodejs/node
November 19, 2018 - Version: v10.13.0 Platform: Linux dcloud_dev 3.13.0-88-generic #135-Ubuntu SMP Wed Jun 8 21:10:42 UTC 2016 x86_64 GNU/Linux Subsystem: I use the conversion to the hexadecimal number buffer as follows Buffer.from(number.toString(16), 'hex...
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The Web Dev
thewebdev.info › home › how to display node.js raw buffer data as hex string?
How to display Node.js raw Buffer data as Hex string? - The Web Dev
March 3, 2022 - We call toString with 'hex' to return a hex version of the raw buffer data. To display Node.js raw Buffer data as Hex string, we can use the buffer toString method.
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Readthedocs
node.readthedocs.io › en › latest › api › buffer
Buffer - node - Read the Docs
'hex' - Encode each byte as two hexadecimal characters. Creating a typed array from a Buffer works with the following caveats: The buffer's memory is copied, not shared. The buffer's memory is interpreted as an array, not a byte array. That is, new Uint32Array(new Buffer([1,2,3,4])) creates ...
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Stack Overflow
stackoverflow.com › questions › 49220715 › javascript-convert-buffer-to-hex
node.js - JavaScript Convert Buffer to Hex - Stack Overflow
Top answer
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8

This should convert your buffer to hex:

b.toString('hex');
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0

For whoever getting the warning Invalid number of arguments, expected 0 with the solution proposed by @TwistedOwl, here a solution to get rid of the warning:

Buffer.from(b).toString('hex');
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Mastering JS
masteringjs.io › tutorials › node › buffer-to-string
Using the Buffer `toString()` Function in Node.js - Mastering JS
August 21, 2020 - Node.js buffers have a `toString()` method you can use to convert raw data into various encodings, like hex and base64. Here's what you need to know.
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Using Buffers in Node.js - w3resource<
November 13, 2023 - Here is an example : The buffer ... set the octet at index. The values refer to individual bytes, the legal range is between 0x00 and 0xFF hex or 0 and 255....
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MojoAuth
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Stack Overflow
stackoverflow.com › questions › 18880301 › node-js-convert-hexadecimal-number-to-bytearray
buffer - Node.js convert hexadecimal number to byteArray - Stack Overflow
Top answer
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177

In new versions of node (6+) the new Buffer() interface is deprecated. Use:

Buffer.from("250001000192CD0000002F6D6E742F72", "hex")

instead.

Find more info on this using this link below https://nodejs.org/api/buffer.html#buffer_static_method_buffer_from_string_encoding

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79
new Buffer("250001000192CD0000002F6D6E742F72", "hex")
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Node-RED
discourse.nodered.org › general
Help with creating a buffer of hex bytes from a string of hex words - #8 by ristomatti - General - Node-RED Forum
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3
[image] jeffreys: but I am stuck on how to get from the above to this format with function code So you realise you can inject a buffer from the inject node right? But if you want to convert a string like "0201 0141 4000 0841 1E90 0000 0000 8203 45" to a buffer then you can do this... msg.ol…
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2
This should be a piece of cake to you @Steve-Mcl, right? :wink:
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GitHub
github.com › nodejs › node › issues › 18231
Any way to decode a buffer containing hex into another buffer? · Issue #18231 · nodejs/node
January 18, 2018 - Buffer.transcode looks promising but I'm not sure it supports hex? ... bufferIssues and PRs related to the buffer subsystem.Issues and PRs related to the buffer subsystem.feature requestIssues that request new features to be added to Node.js.Issues that request new features to be added to Node.js.
Author: nodejs
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Fuad Olatunji
blog.fuadolatunji.me › how-nodejs-bufferfromstr-hex-might-be-implemented
How Node.js Buffer.from(str, 'hex') might be implemented?
December 13, 2024 - Subscribe to the newsletter. Get new posts in your inbox. /** * @param {string} b * @returns {string} */ const btoa = (b) => { let s = ''; const bytes = new Uint8Array(b.split('').map(x => x.charCodeAt(0))); const ALPHABET_TABLE = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz01234567... ... tmux -V &> /dev/null if [[ $? -eq 0 ]]; then function clear_tmux_scrollback_buffer() { tmux clear-history } zle -N clear_tmux_scrollback_buffer bindkey "^[^L" clear_tmux_scrollback_buffer fi https://github.com/fuadop/zsh-conf...
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Stack Overflow
stackoverflow.com › questions › 52261494 › hex-to-string-string-to-hex-conversion-in-nodejs › 52261621
node.js - Hex to String & String to Hex conversion in nodejs - Stack Overflow
Top answer
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33

You need to use Buffer.from() for decoding as well. Consider writing a higher-order function to reduce the amount of repeated code:

const convert = (from, to) => str => Buffer.from(str, from).toString(to)
const utf8ToHex = convert('utf8', 'hex')
const hexToUtf8 = convert('hex', 'utf8')

hexToUtf8(utf8ToHex('dailyfile.host')) === 'dailyfile.host'
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GitHub
github.com › nodejs › node › commit › 17c4187949
buffer: optimize hex_decode · nodejs/node@17c4187
October 26, 2016 - const common = require('../common.js'); 4 · + 5 · + const bench = common.createBenchmark(main, { 6 · + len: [0, 1, 64, 1024], 7 · + n: [1e7] 8 · + }); 9 · + 10 · + function main(conf) { 11 · + const len = conf.len | 0; 12 · + const n = conf.n | 0; 13 · + const buf = Buffer.alloc(len); 14 · + 15 · + for (let i = 0; i < buf.length; i++) 16 · + buf[i] = i & 0xff; 17 · + 18 · + const hex = buf.toString('hex'); 19 ·
Author: nodejs
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GitHub
github.com › nodejs › node › commit › d944fa71dd
doc: explain `hex` encoding in Buffer API · nodejs/node@d944fa7
March 17, 2020 - Copy file name to clipboardExpand ... * `'binary'`: Alias for `'latin1'`. 205 · 205 · 206 · - * `'hex'`: Encode each byte as two hexadecimal characters....
Author: nodejs
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GitHub
github.com › nodejs › node › commit › 6055134db6
doc: explain `hex` encoding in Buffer API · nodejs/node@6055134
February 17, 2020 - Copy file name to clipboardExpand ... * `'binary'`: Alias for `'latin1'`. 205 · 205 · 206 · - * `'hex'`: Encode each byte as two hexadecimal characters....
Author: nodejs
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Stack Exchange
ethereum.stackexchange.com › questions › 61624 › how-to-convert-a-uint-to-64-byte-hex-string-using-node-js
nodejs - How to convert a uint to 64 byte hex string using Node.js? - Ethereum Stack Exchange
Top answer
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2

Sir, If my uint is 10,how to convert 10 to '0x000000000000000000000000000000000000000000000000000000000000000a' by using Node.js?

You can use web3.toHex(number) to convert decimal number to hex then using web3.utils.padLeft("0x0abcdef", 64) to format the hex string to a 64 byte length hex

https://web3js.readthedocs.io/en/1.0/web3-utils.html#padleft

and reverse it from '0x000000000000000000000000000000000000000000000000000000000000000a' to uint 10 ?

just simply use web3.toDecimal() function to convert any hex string to decimal

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0

Got it. My example is：

var a = 10
console.log(a); //output ：10
var b = web3.utils.toHex(a);  
console.log(b); //output ：0xa
var c = web3.utils.padLeft(b, 64);
console.log(c);  //output ：0x000000000000000000000000000000000000000000000000000000000000000a
var d = web3.utils.toDecimal(c)
console.log(d); //output ：10