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The Number Base Converter converts numeric values between different bases (radixes): binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16). It supports arbitrary precision using JavaScript’s BigInt for large numbers.

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Use Cases

  • Programming and debugging - Convert between hex, decimal, and binary
  • Network engineering - Convert IP addresses and subnet masks
  • Color codes - Convert hex color codes to RGB decimal values
  • Bit manipulation - Work with binary representations
  • Memory addresses - Convert between hex and decimal addresses
  • Low-level programming - Octal file permissions, bitmasks

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How It Works

The tool accepts a number in any base (2-36) and displays its equivalent in binary, octal, decimal, and hexadecimal:
  1. Input format: value|base (e.g., FF|16 for hex, 1010|2 for binary)
  2. Default base: If no base is specified, assumes decimal (base 10)
  3. Output: Shows conversions to binary, octal, decimal, and hex
The tool uses BigInt for arbitrary precision, so it can handle very large numbers (thousands of digits) without loss of precision.

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Input Format

Format: number|base
  • number: The numeric value (using digits valid for the specified base)
  • base: The base/radix (2-36)
  • If base is omitted, assumes base 10

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Valid Digit Ranges by Base

BaseValid DigitsExample
2 (Binary)0-11010
8 (Octal)0-7755
10 (Decimal)0-9255
16 (Hex)0-9, A-FFF (case-insensitive)
36 (Max)0-9, A-ZZ = 35

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Output Format

Always shows four representations: 
Binary:  11111111
Octal:   377
Decimal: 255
Hex:     FF

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Examples

Input:
FF|16

Output:
Binary:  11111111
Octal:   377
Decimal: 255
Hex:     FF

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Technical Details

Located in lib/tools/engine.ts:506-518
The tool implements a custom base parser using BigInt for arbitrary precision: 
function parseBase(value: string, base: number): bigint {
  let acc = 0n;
  for (const ch of value.toLowerCase()) {
    const digit = /* convert char to digit value */;
    acc = acc * BigInt(base) + BigInt(digit);
  }
  return acc;
}

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Supported Bases

  • Range: 2 to 36
  • Digits:
    • 0-9: Values 0-9
    • A-Z: Values 10-35 (case-insensitive)

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Negative Numbers

Negative numbers are supported: 
Input: -10|10
Output:
Binary:  -00001010
Decimal: -10
Hex:     -A

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Binary Padding

Binary output is padded to 8 bits (1 byte) minimum: 
Input: 5
Binary:  00000101  (padded to 8 bits)

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Common Use Cases

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RGB Color Codes

Convert hex color codes to decimal RGB values: 
Hex: #FF5733 → Split into FF, 57, 33

FF|16 → 255 (Red)
57|16 → 87  (Green)
33|16 → 51  (Blue)

RGB: rgb(255, 87, 51)

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Unix File Permissions

Convert octal permissions to binary/decimal: 
755|8 → Decimal 493 → Binary 111101101

7 (owner)   = 111 = rwx (read, write, execute)
5 (group)   = 101 = r-x (read, execute)
5 (others)  = 101 = r-x (read, execute)

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Memory Addresses (Hex to Decimal)

0x1A2B|16 → Decimal 6699

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Subnet Masks

Convert CIDR notation to binary: 
255.255.255.0 = /24

255|10 → Binary 11111111
0|10   → Binary 00000000

Full mask: 11111111.11111111.11111111.00000000

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Advanced Examples

Input:
ZZ|36

Output:
Binary:  10010010001
Octal:   2221
Decimal: 1295
Hex:     50F

Note: Base 36 uses 0-9 and A-Z (Z=35)

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Error Handling

If you enter a digit that’s invalid for the specified base (e.g., 9 in base 8, or G in base 16), you’ll get an error: “Invalid digit ‘X’ for base Y.”

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Common Errors

ErrorCauseFix
Invalid digit ‘2’ for base 2Used digit outside base rangeUse only 0-1 for binary
Invalid digit ‘G’ for base 16Hex only uses 0-FUse A-F (G is invalid)
Base must be between 2 and 36Invalid base specifiedUse base 2-36

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Tips and Tricks

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Quick Hex to Decimal

FF|16 = 255
100|16 = 256
1000|16 = 4096

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Powers of 2 (Binary)

1|2      = 1
10|2     = 2
100|2    = 4
1000|2   = 8
10000|2  = 16
100000|2 = 32

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Octal Shortcuts

10|8  = 8
100|8 = 64
777|8 = 511

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