Hexadecimal to Decimal Converter
Convert hexadecimal numbers to decimal (base 10) instantly. Supports 0x prefix and large numbers.
How to Convert Hex to Decimal
Each hexadecimal digit represents a power of 16. To convert:
- Identify each hex digit (0-9, A-F where A=10, F=15)
- Multiply each digit by 16^position (right to left, starting at 0)
- Sum all the results
Example: Convert 0xFF to decimal:
- F (15) × 16¹ = 15 × 16 = 240
- F (15) × 16⁰ = 15 × 1 = 15
- Result: 240 + 15 = 255
Code Examples
const hex = "ff";
const decimal = parseInt(hex, 16); // 255
// For large numbers, use BigInt:
const bigHex = "ffffffffffffffff";
const bigDecimal = BigInt("0x" + bigHex);Frequently Asked Questions
How do I convert hex to decimal?
Multiply each hex digit by its position value (16^n) and sum the results. For example, FF = (15 × 16¹) + (15 × 16⁰) = 240 + 15 = 255.
What does the 0x prefix mean?
The 0x prefix indicates a hexadecimal number in most programming languages (C, JavaScript, Python). It helps distinguish hex from decimal: 10 is ten, but 0x10 is sixteen.
Can I convert large hex numbers?
Yes! This converter supports arbitrarily large numbers using BigInt. It can handle hex values beyond the standard 64-bit integer limit.