Complete guide
Hex calculator with arithmetic, decimal and binary conversion
Add, subtract, multiply or divide hexadecimal integers, or convert hex and decimal directly. Every result includes uppercase hex, decimal and binary.
What hexadecimal means
Hexadecimal is base 16. After 9, the digits A, B, C, D, E and F represent decimal 10 through 15.
Hex arithmetic
The same carrying and borrowing ideas used in decimal apply, but each column has sixteen possible digit values.
Hex and binary
Because 16 equals 2⁴, each hexadecimal digit maps exactly to four binary bits.
A₁₆=1010₂=10₁₀FF₁₆=11111111₂=255₁₀Hex and decimal conversion
Multiply each digit value by 16 raised to its position. Decimal-to-hex repeatedly divides by sixteen and reads the remainders backward.
Worked addition example
2A₁₆ is 42 decimal and 10₁₆ is 16. Their sum is 58 decimal, written 3A₁₆.
Signed and color-code limits
A minus sign denotes a mathematical negative integer. This tool does not infer bit width, memory layout, CSS colors or alpha channels.
Hex digits above nine
| Hex | Decimal | Binary |
|---|---|---|
| A | 10 | 1010 |
| B | 11 | 1011 |
| C | 12 | 1100 |
| D | 13 | 1101 |
| E | 14 | 1110 |
| F | 15 | 1111 |
Frequently asked questions
Can I use lowercase hex?
Yes. Output is normalized to uppercase.
Do I need to type 0x?
No. The optional prefix is accepted but not required.
What is FF in decimal?
It is 255.
Does division show a remainder?
Yes.
Can results exceed 32 bits?
Yes. BigInt provides exact integer arithmetic within the input-length limit.
Does this calculate CSS colors?
No. It handles hexadecimal integers.
What to keep in mind
Whole signed integers only, up to 128 hexadecimal digits. Division returns quotient and remainder; fractional hex and fixed-width two's-complement interpretation are outside scope.
Results display up to 8 decimal places; exported numbers preserve calculation precision. This is a calculation summary, not an official certificate.