Hex Calculator
Quickly find your Hex arithmetic with our free Hex Calculator. Simple, fast, and accurate.
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What is a Hex Calculator?
A Hex Calculator converts numbers between hexadecimal (base 16), decimal (base 10), binary (base 2), and octal (base 8). It is indispensable for programmers, network engineers, and anyone working with low-level computing.
How to convert decimal to hex manually (the formula)
Repeatedly divide the decimal number by 16. Record the remainder at each step, converting values 10–15 to the letters A–F. Read the remainders from the last to the first to get the hex value.
Example calculation
Convert 255 to hex. 255 ÷ 16 = 15 remainder 15 (F), 15 ÷ 16 = 0 remainder 15 (F). Reading from bottom to top: FF. So 255 in hex is FF.
Common mistakes
- Forgetting to use letters for 10–15 — In hex, A=10, B=11, C=12, D=13, E=14, F=15. Never use two-digit numbers in a single hex digit.
- Reading remainders in the wrong order — The last remainder is the most significant (leftmost) hex digit.
- Confusing hex with decimal — The number "10" means sixteen in hex, not ten. Always check the base.
Frequently asked questions
What is hexadecimal?
Hexadecimal (hex) is a base-16 number system using digits 0-9 and letters A-F.
How do I convert decimal to hex?
Repeatedly divide by 16 and read the remainders, converting 10-15 to A-F.
What is FF in decimal?
FF in hexadecimal equals 255 in decimal.
Why is hex used in computing?
Hex provides a compact way to represent binary data; one hex digit equals four binary digits.
How do I add hex numbers?
Add column by column in base 16, carrying when a column exceeds 15.