Decimal to Hex Converter

Decimal to hexadecimal conversion is the process of expressing a base-10 number (using digits 0–9) in base-16 notation (using digits 0–9 and letters A–F for values 10–15). For example, the decimal number 255 converts to FF in hexadecimal. Each hex digit represents exactly four binary bits, making hex a compact way to express binary data.

Hexadecimal is widely used in computing because it maps cleanly to binary — each hex digit represents exactly 4 bits (a nibble). This makes it far more concise than binary while still being easy to convert. You'll encounter hex in memory addresses, color codes (#RRGGBB), error codes, and network MAC addresses.

To convert manually, repeatedly divide the decimal number by 16 and record the remainder at each step. Remainders of 10–15 are written as A–F. Once the quotient reaches 0, read the remainders in reverse order to get the hex result. For example, 255 ÷ 16 = 15 remainder 15 (F), then 15 ÷ 16 = 0 remainder 15 (F), giving FF.

Hexadecimal uses 16 symbols: 0–9 represent values zero through nine, and A, B, C, D, E, F represent values 10, 11, 12, 13, 14, and 15 respectively. Each position in a hex number represents a power of 16, so the rightmost digit is 16⁰ (1s place), the next is 16¹ (16s place), and so on.

This converter handles non-negative integers within the safe integer range of JavaScript (up to 2⁵³ − 1, or 9,007,199,254,740,991). For very large numbers beyond 64-bit integer range, specialized big-integer libraries would be required. Most practical use cases — such as IP addresses, color codes, and memory values — fall well within this range.

A common misconception is that hex numbers like 'FF' or 'AB' are letters rather than numeric values — they are simply digit symbols for 15 and 11 respectively. Another misconception is that hex is only used for colors; in reality it appears throughout low-level programming, networking, and hardware configuration. Hex is not a different type of number, just a different way of writing the same value.

The step-by-step table below the result shows each division-by-16 iteration: the starting dividend, the integer quotient, and the remainder in both decimal and hex form. Reading the hex remainders from the bottom of the table upward gives you the final hexadecimal number, which matches the result shown at the top.

To convert hexadecimal back to decimal, multiply each hex digit by 16 raised to its positional power and sum the results. For example, hex 2D = 2×16¹ + 13×16⁰ = 32 + 13 = 45. You can use our Hex to Decimal Converter to do this automatically.