object-sizeof

What is object-sizeof?

The object-sizeof npm package is used to calculate the approximate memory usage of JavaScript objects. It helps developers understand the memory footprint of their data structures, which can be crucial for optimizing performance and managing resources effectively.

What are object-sizeof's main functionalities?

Calculate size of a simple object

This feature allows you to calculate the memory size of a simple JavaScript object. The code sample demonstrates how to use the `sizeof` function to get the size of an object with basic key-value pairs.

const sizeof = require('object-sizeof');
const obj = { a: 1, b: 2, c: 3 };
console.log(sizeof(obj)); // Outputs the size of the object in bytes

Calculate size of a nested object

This feature allows you to calculate the memory size of a nested JavaScript object. The code sample shows how to use the `sizeof` function to get the size of an object with nested structures.

const sizeof = require('object-sizeof');
const nestedObj = { a: 1, b: { c: 2, d: { e: 3 } } };
console.log(sizeof(nestedObj)); // Outputs the size of the nested object in bytes

Calculate size of an array

This feature allows you to calculate the memory size of a JavaScript array. The code sample demonstrates how to use the `sizeof` function to get the size of an array.

const sizeof = require('object-sizeof');
const arr = [1, 2, 3, 4, 5];
console.log(sizeof(arr)); // Outputs the size of the array in bytes

Calculate size of a complex object

This feature allows you to calculate the memory size of a complex JavaScript object that includes various data types. The code sample shows how to use the `sizeof` function to get the size of an object with mixed data types.

const sizeof = require('object-sizeof');
const complexObj = { a: 1, b: [1, 2, 3], c: { d: 'string', e: true } };
console.log(sizeof(complexObj)); // Outputs the size of the complex object in bytes

Other packages similar to object-sizeof

sizeof

The `sizeof` package provides similar functionality to `object-sizeof` by calculating the approximate memory usage of JavaScript objects. It is straightforward to use and offers a simple API for determining the size of various data structures.

object-size

The `object-size` package is another alternative that calculates the size of JavaScript objects. It provides a similar feature set to `object-sizeof` and can be used to measure the memory footprint of different data structures.

README

object-sizeof

Get size of a JavaScript object in Bytes - Node.js

Node.js version uses the Buffer.from(objectToString) method to convert the object's string representation to a buffer, and then it uses the byteLength property to obtain the buffer size in bytes.

Complex types support

• Map

Get size of a JavaScript object in Bytes - Browser

For the browser, the calculation takes an object as an argument. It uses a combination of recursion and a stack to iterate through all of its properties, adding up the number of bytes for each data type it encounters.

Please note that this function will only work in some cases, especially when dealing with complex data structures or when the object contains functions.

Coding standards

Project uses JavaScript Standard Style. Code coverage reports done using Codecov.io.

Get size of a JavaScript object in Bytes - version 1.x

JavaScript does not provide sizeof (like in C), and programmer does not need to care about memory allocation/deallocation.

However, according to ECMAScript Language Specification, each String value is represented by 16-bit unsigned integer, Number uses the double-precision 64-bit format IEEE 754 values including the special "Not-a-Number" (NaN) values, positive infinity, and negative infinity.

Having this knowledge, the module calculates how much memory object will allocate.

Limitations

Please note, that V8 which compiles the JavaScript into native machine code, is not taken into account, as the compiled code is additionally heavily optimized.

Installation

npm install object-sizeof

Examples

import sizeof from 'object-sizeof'

// 2B per character, 6 chars total => 12B
console.log(sizeof({ abc: 'def' }))

// 8B for Number => 8B
console.log(sizeof(12345))

const param = {
  a: 1,
  b: 2,
  c: {
    d: 4
  }
}
// 4 one two-bytes char strings and 3 eighth-bytes numbers => 32B
console.log(sizeof(param))

Licence

The MIT License (MIT)

Copyright (c) 2015, Andrei Karpushonak aka @miktam