How to use it
A practical browser-based utility for quick checks, planning and clearer work. Enter the requested values, review the result and keep the assumptions with your record.
- Enter the source values carefully.
- Select any required options and run the calculation.
- Review the result, formula and worked example before using it in a decision.
Formula
The method used by this tool is rem = pixels ÷ root font size. Keep the source values and units with the result so another person can reproduce the calculation.
Worked example
24px at 16px base → 1.5rem. This example demonstrates the sequence; your result depends on the values and options you enter.
Excel guidance
Use this workbook approach: =A2/B2. Format percentage results as Percentage, dates as dates, and financial values with the correct currency. Avoid rounding intermediate steps.