fromBase

Converts a string representation of a number in any base (2-36) to decimal. Parses a string containing digits and letters representing a number in the specified base and converts it to its decimal (base 10) equivalent. Supports negative numbers and uses case-insensitive letter parsing for bases greater than 10.

Signature

const fromBase: (value: string, base: number) => number

Parameters

Name	Type	Description
value	-	String representation of the number (must be non-empty)
base	-	Numeric base from 2 to 36 (2=binary, 8=octal, 16=hex, etc.)

Returns

Decimal number equivalent of the input

Examples

Common base conversions

import { fromBase } from '@winglet/common-utils';

// Binary (base 2)
console.log(fromBase('1010', 2)); // 10
console.log(fromBase('1111', 2)); // 15

// Octal (base 8)
console.log(fromBase('17', 8)); // 15
console.log(fromBase('777', 8)); // 511

// Hexadecimal (base 16)
console.log(fromBase('FF', 16)); // 255
console.log(fromBase('1A3', 16)); // 419

Advanced base conversions and edge cases

// High bases with letters
console.log(fromBase('ZZ', 36)); // 1295 (35*36 + 35)
console.log(fromBase('10', 36)); // 36

// Negative numbers
console.log(fromBase('-1010', 2)); // -10
console.log(fromBase('-FF', 16)); // -255

// Case insensitive
console.log(fromBase('abc', 16)); // 2748 (same as 'ABC')
console.log(fromBase('ABC', 16)); // 2748

Playground

import { fromBase } from '@winglet/common-utils';

// Binary (base 2)
console.log(fromBase('1010', 2)); // 10
console.log(fromBase('1111', 2)); // 15

// Octal (base 8)
console.log(fromBase('17', 8)); // 15
console.log(fromBase('777', 8)); // 511

// Hexadecimal (base 16)
console.log(fromBase('FF', 16)); // 255
console.log(fromBase('1A3', 16)); // 419

Notes

Supported Bases:

• Base 2 (binary): digits 0-1
• Base 8 (octal): digits 0-7
• Base 10 (decimal): digits 0-9
• Base 16 (hexadecimal): digits 0-9, A-F
• Base 36 (maximum): digits 0-9, A-Z

Use Cases:

• Converting user input from different numeric systems
• Parsing configuration files with different base representations
• Educational tools for teaching number systems
• Cryptography and encoding/decoding operations
• Computer science algorithms requiring base conversion
• Data format parsing (hex colors, binary flags, etc.)

Performance: O(n) time complexity where n is the length of the input string. Space complexity is O(1) excluding input string.