How to Calculate Hex to Decimal: A Step-by-Step Guide
Converts hexadecimal to decimal.
These calculations come up in school, at work and in daily life, from PSLE and O-Level practice to measuring a room for new flooring. Doing them by hand builds understanding, and a calculator lets you check the answer instantly.
What you need
- Hexadecimal number
Step by step
- Enter the hexadecimal number.
- The results update as you type, or press Calculate.
- Read the decimal first, then the supporting figures below it.
The formula
Sum each digit × 16^position.
Worked example
For example, with these inputs:
- Hexadecimal number: FF
the calculator returns:
- Decimal: 255
Practical tips
- Round only at the final step to avoid accumulated rounding errors.
- For exam work, show your method; marks are often given for working, not just the answer.
- Estimate the answer roughly first so you can spot a result that is clearly wrong.
- When numbers are very large or small, scientific notation makes them easier to compare.
Background
These calculations appear throughout the Singapore syllabus, from primary school percentages and fractions to secondary school algebra and geometry. Understanding the formula makes problem sums easier because you can recognise which quantity is missing.
A quick mental estimate before calculating is a powerful check. If a room's floor area comes out at 4,000 square metres or a percentage comes out above 100% when it should not, you know to look again.
Rounding is a common source of small errors. Keep full precision during intermediate steps and round only the final answer to the number of decimal places or significant figures the question asks for.
Related calculations
- Volume of a Cylinder Calculator: Calculates the volume of a cylinder from the measurements you enter.
- Volume of a Cone Calculator: Calculates the volume of a cone from the measurements you enter.
- Volume of a Square Pyramid Calculator: Calculates the volume of a square pyramid from the measurements you enter.
- Volume of a Hemisphere Calculator: Calculates the volume of a hemisphere from the measurements you enter.
Want to skip the arithmetic? The free Hex to Decimal Converter does all of this instantly and updates as you type.
Run your own numbers: Hex to Decimal Converter