Number Converters · Browser · Free

Decimal to Hexadecimal Converter

Type a decimal (base 10) number and get the same value written in hexadecimal (base 16), with the binary and octal forms shown alongside. A sign and a fractional point are accepted, and several numbers separated by spaces are converted one by one.

How this converter works

Decimal is base 10 and hexadecimal is base 16, so this converter rewrites one value in the other spelling. Hexadecimal needs six more single digits than decimal does, and letters stand in for them, printed uppercase: the table lists 10 as A and 15 as F. The binary and octal forms of the same number are shown with the answer.

There is one text field. A sign and a fractional point are accepted, and several numbers separated by spaces are converted one by one. Nothing is worked out until you press Convert, and the result then appears in a card below the button. Copy writes the result and its unit to the clipboard, and Clear resets the form.

Decimal to hexadecimal formula

Both systems are positional: each digit is taken with the place it sits in, and each place is worth the base times the place to its right. In decimal the base is 10. In hexadecimal the base is 16, so the places are worth ones, then sixteens, then a place sixteen times the sixteens again; the table row 256 = 100 is where that third place begins.

To read a hexadecimal number back, take each digit together with its place and add. The row 31 = 1F holds one group of sixteen plus F, the digit the table gives for 15. The row 255 = FF fills the sixteens place and the ones place with F, and one more unit pushes the value to the 256 = 100 row. In 1024 = 400 the digit 4 sits in that third place with zeros in the two places before it.

Digits to the right of a fractional point follow the same positional rule, with the place shrinking by a factor of sixteen at each step to the right. A sign in front of the number carries over as it is.