Convert Hexadecimal to Decimal

Convert hexadecimal to decimal instantly, e.g. FF to 255 — free online hex converter.

About

About the Hexadecimal to Decimal Converter

Code and hardware datasheets are full of hex literals — colour values, memory addresses, error codes — and converting hex to decimal turns them back into the ordinary numbers most people find easier to compare or do arithmetic with.

Each hex digit is worth 16 times the one to its right, so 1F4 is 1×256 + 15×16 + 4 = 500. The same works for colour codes one channel at a time: #1E90FF splits into 1E, 90 and FF, which are 30, 144 and 255 — the RGB values of that shade of blue.

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Guide

Using the Hexadecimal to Decimal Converter

  1. 1

    Step 1

    Hexadecimal is already selected below as the input base.

  2. 2

    Step 2

    Type your hex digits (0-9, A-F) into the value box.

  3. 3

    Step 3

    The result table fills in instantly — the decimal value sits alongside binary, octal and hex all at once.

  4. 4

    Step 4

    For a quick manual check, multiply each hex digit by the matching power of 16 (counting from the right, starting at 16^0) and add the results.

  • Converts hex to decimal as you type — upper or lower case, with or without 0x
  • Reads colour codes one channel at a time: type each pair, like 1E, without the #
  • Handles large values such as 32-bit error codes and addresses exactly
  • Shows the value in binary, octal, decimal, hexadecimal and base 36 at once, plus any custom base from 2 to 36
  • Exact for whole numbers up to 9,007,199,254,740,991, and tells you when a number is too large
  • Runs entirely in your browser — free, with no sign-up and no limit

Web designers

Designers turn a hex colour into the RGB numbers an app or stylesheet wants.

IT support

Support staff convert a Windows error code like 0x80070005 into the decimal form some logs show.

Programmers

Programmers read hex offsets and sizes from a debugger as ordinary numbers.

Students

Students check place-value conversions in base 16.

Popular base conversions

Binary Octal Binary Decimal Binary Hexadecimal Octal Binary Octal Decimal Octal Hexadecimal Decimal Binary Decimal Octal Decimal Hexadecimal Hexadecimal Binary Hexadecimal Octal

Examples

Hexadecimal to Decimal examples

4 worked examples

01

A colour or byte value, FF

Hex FF converts to decimal 255 — the maximum value a single byte can hold, and a common full-brightness colour channel value.

02

A smaller value, 2A

Hex 2A converts to decimal 42, computed as (2×16¹)+(10×16⁰) = 32+10 = 42.

03

A round number, 100

Hex 100 converts to decimal 256, since (1×16²)+(0×16¹)+(0×16⁰) = 256.

04

A memory-style address

0x1A3F converts to 6719 — the 0x prefix is removed for you.

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FAQ

Frequently asked questions

Quick answers to common questions about the Hexadecimal to Decimal Converter.

How do I convert hex to decimal?

Type your hex value above, with hexadecimal selected as the input base. The decimal value appears instantly in the results table — nothing is uploaded anywhere.

How do you convert hex to decimal by hand?

Multiply each digit by 16 raised to its position (from the right, starting at 0) and add them up: FF is (15×16¹)+(15×16⁰) = 240+15 = 255.

What is FF in decimal?

FF in hex is 255 in decimal — the maximum value a single byte can hold, and a common colour or opacity value in code.

Is this hex to decimal converter free?

Yes. It's free, with no sign-up and no limit on how many numbers you convert.

Can I convert decimal back to hex?

Yes — the same converter works in both directions. Select decimal as the input base instead, or use the dedicated decimal to hex converter page.

How large a hex value can I convert?

Up to 9,007,199,254,740,991 in decimal terms — beyond that the conversion won't be exact, and the tool will tell you so.

How do I convert a hex colour like #FF5733 to RGB?

Convert it in pairs: FF is 255, 57 is 87 and 33 is 51, giving rgb(255, 87, 51). Enter each pair here, or use the HEX to RGB Converter to do all three at once.

Can I paste a value with 0x in front?

Yes. The 0x prefix used in code and memory addresses is stripped automatically, so 0x1A3F gives 6719.

What is hex 7FFFFFFF in decimal?

2,147,483,647 — the largest value a signed 32-bit integer can hold, which is why it often shows up as a limit in databases and older software.

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