hexadecimal to decimal conversion calculator

Hexadecimal numbers appear everywhere in computing: memory addresses, color codes, low-level programming, and debugging output. This calculator helps you quickly convert any base-16 value into a base-10 decimal number, while also showing the logic behind the result.

What is hexadecimal?

Hexadecimal is a number system with base 16. That means each digit position represents a power of 16 (not 10). It uses sixteen symbols total:

• 0–9 for values zero through nine
• A–F for values ten through fifteen

So, the hex digit A equals decimal 10, and F equals decimal 15.

How to use this hexadecimal to decimal conversion calculator

1. Type your hex value in the input field (for example: 7B, FF, or 0x2A).
2. Click Convert to Decimal.
3. Read the decimal result and (for shorter inputs) a step-by-step expansion.

You can also press the Enter key to convert instantly.

Hex digit reference table

Hex	Decimal	Hex	Decimal
0	0	8	8
1	1	9	9
2	2	A	10
3	3	B	11
4	4	C	12
5	5	D	13
6	6	E	14
7	7	F	15

Manual conversion method (base 16 to base 10)

To convert hex to decimal manually:

1. Starting from the right, assign powers of 16: 16⁰, 16¹, 16², and so on.
2. Convert each hex digit to its decimal value.
3. Multiply each digit value by its positional power of 16.
4. Add all contributions together.

Example: Convert 2F to decimal

• 2 is in the 16¹ place → 2 × 16 = 32
• F is in the 16⁰ place → 15 × 1 = 15
• Total = 32 + 15 = 47

Example: Convert 1A3 to decimal

• 1 × 16² = 1 × 256 = 256
• A × 16¹ = 10 × 16 = 160
• 3 × 16⁰ = 3 × 1 = 3
• Total = 256 + 160 + 3 = 419

Common input mistakes to avoid

• Using letters outside A-F (such as G, H, or Z).
• Adding decimal points or commas inside the hex value.
• Confusing the letter O with zero 0.
• Forgetting that hex is base 16 and decimal is base 10.

Where hex-to-decimal conversion is useful

• Software development and debugging
• Understanding memory addresses
• Reading binary/hex dumps
• Cybersecurity and digital forensics workflows
• Learning computer architecture and data representation

FAQ

Can I type lowercase hex letters?

Yes. The calculator accepts both uppercase and lowercase letters (A-F and a-f).

Can I include the 0x prefix?

Yes. Inputs like 0xFF are accepted automatically.

Does it work with very large hexadecimal values?

Yes. The converter uses BigInt-based logic, which supports very large integers beyond normal JavaScript number limits.