JavaScript Typed Array Reference

Complete reference guide for all typed array types and properties

📚 Typed Array Reference Guide

This comprehensive reference covers all typed array types, their properties, and use cases. Use this as your go-to guide for typed array development. 


// Quick reference example
const int8 = new Int8Array(4);        // 8-bit signed integers
const uint8 = new Uint8Array(4);      // 8-bit unsigned integers
const float32 = new Float32Array(4);  // 32-bit floating point
console.log(int8.BYTES_PER_ELEMENT);  // 1

Output:

1

All Typed Array Types

🔢

Int8Array

8-bit signed integers (-128 to 127) 

new Int8Array(4)
// 1 byte per element
âž•

Uint8Array

8-bit unsigned integers (0 to 255) 

new Uint8Array(4)
// 1 byte per element
🎯

Int16Array

16-bit signed integers (-32,768 to 32,767) 

new Int16Array(4)
// 2 bytes per element
🔄

Float32Array

32-bit floating point numbers 

new Float32Array(4)
// 4 bytes per element

🔹 Complete Type Reference

All available typed array types with their specifications: 

// 8-bit types
const int8 = new Int8Array([127, -128]);        // -128 to 127
const uint8 = new Uint8Array([255, 0]);         // 0 to 255
const uint8Clamped = new Uint8ClampedArray([300, -10]); // Clamped 0-255

// 16-bit types  
const int16 = new Int16Array([32767, -32768]);  // -32,768 to 32,767
const uint16 = new Uint16Array([65535, 0]);     // 0 to 65,535

// 32-bit types
const int32 = new Int32Array([2147483647]);     // -2^31 to 2^31-1
const uint32 = new Uint32Array([4294967295]);   // 0 to 2^32-1

// Floating point types
const float32 = new Float32Array([3.14159]);    // 32-bit float
const float64 = new Float64Array([Math.PI]);    // 64-bit float

// BigInt types (64-bit)
const bigInt64 = new BigInt64Array([9007199254740991n]);
const bigUint64 = new BigUint64Array([18446744073709551615n]);

Memory Usage:

Int8Array: 1 byte per element

Int16Array: 2 bytes per element

Int32Array: 4 bytes per element

Float64Array: 8 bytes per element

🔹 Properties Reference

Essential properties available on all typed arrays: 

const arr = new Float32Array([1.5, 2.7, 3.9]);

// Static properties
console.log(Float32Array.BYTES_PER_ELEMENT); // 4
console.log(Float32Array.name);              // "Float32Array"

// Instance properties
console.log(arr.length);        // 3 (number of elements)
console.log(arr.byteLength);    // 12 (total bytes: 3 * 4)
console.log(arr.byteOffset);    // 0 (offset in buffer)
console.log(arr.buffer);        // ArrayBuffer object

// Constructor reference
console.log(arr.constructor === Float32Array); // true

Output:

4

"Float32Array"

3

12

0

true

🔹 Method Categories

Typed arrays inherit methods from Array.prototype: 

const numbers = new Int16Array([10, 20, 30, 40, 50]);

// Accessor methods (don't modify original)
console.log(numbers.slice(1, 3));     // Int16Array [20, 30]
console.log(numbers.indexOf(30));     // 2
console.log(numbers.includes(40));    // true

// Iteration methods
const doubled = numbers.map(x => x * 2);
const evens = numbers.filter(x => x % 20 === 0);
const sum = numbers.reduce((a, b) => a + b, 0);

console.log(doubled);  // Int16Array [20, 40, 60, 80, 100]
console.log(evens);    // Int16Array [20, 40]
console.log(sum);      // 150

Output:

Int16Array [20, 30]

2

true

Int16Array [20, 40, 60, 80, 100]

Int16Array [20, 40]

150

🔹 Use Case Guide

Choose the right typed array for your needs: 

// Image processing (RGB values 0-255)
const imageData = new Uint8Array(width * height * 3);

// Audio processing (floating point samples)
const audioBuffer = new Float32Array(sampleRate * duration);

// Game coordinates (signed integers)
const positions = new Int16Array([-100, 50, 200, -75]);

// Scientific calculations (high precision)
const measurements = new Float64Array([3.141592653589793]);

// File I/O (byte data)
const fileBytes = new Uint8Array(fileSize);

// Memory-efficient counters (small positive numbers)
const counters = new Uint16Array(1000); // 0 to 65,535

console.log("Image pixel:", imageData[0]);
console.log("Audio sample:", audioBuffer[0]);
console.log("Game position:", positions[0]);

Best Practices:

• Use Uint8Array for binary data and images

• Use Float32Array for graphics and audio

• Use Int32Array for general numeric data

• Use Float64Array for scientific precision

🧠 Test Your Knowledge

Which typed array is best for storing RGB color values (0-255)?