CSS Unit Converter
Use CSS Unit Converter locally in your browser.
Your inputs
Your inputs and files stay on your device.
Your result
A little input. A useful answer.
Enter your values and run the tool to see your result here.
How to use this tool
- Enter values.
- Generate output.
- Copy result.
About CSS Unit Converter
Use this CSS Unit Converter for a clear, copyable result.
Does this tool send my data anywhere?
No. Its calculation or transformation happens on your device.
Using CSS Unit Converter with the right inputs
Use CSS Unit Converter locally in your browser. Start by matching your task to the quantities and options shown below. The definitions of the inputs matter as much as the final number or transformed output; retain the original values so that you can repeat or check the result.
Inputs and options explained
- Value: Enter the numeric value for this quantity using the units or scale shown in the label.
- From: choose Pixels (px), Root em (rem), Em (em), Percent (%).
- To: choose Pixels (px), Root em (rem), Em (em), Percent (%).
- Base font size (px): Enter the numeric value for this quantity using the units or scale shown in the label. The form indicates a minimum of 1.
Example to try in this tool
Use the following sample values to see how the controls and result fit together. They are an illustration of the operation, not recommended values for your own situation.
- Value: 100
- From: Pixels (px)
- To: Pixels (px)
- Base font size (px): 16
Select Convert CSS unit. The result begins with:
Converted CSS unit
100px
This example records the tool’s output for those inputs. Check the method and assumptions against your own task before using a result; reproducing an example is not independent certification of the underlying model.
Interpretation and limitations
Match the physical quantity and unit definition before converting. Similar unit names can refer to different conventions. Keep adequate precision during intermediate calculations, then round for the final use rather than repeatedly rounding each step.
Can I convert between any two units?
Only units representing compatible quantities can be converted directly. Confirm the definition and conditions of the source measurement before interpreting a numerical equivalent.
Before you use the output
- Choose the intended action: Convert CSS unit. Re-run the operation after changing an input or mode so that you are checking the updated result.
- Read the result label and any accompanying explanation. Keep the input values or source file with the output so that a later comparison uses the same assumptions.
- If a result looks unexpected, check units, separators and selected options first. Try a smaller example you can verify rather than repeatedly changing several settings at once.
Questions or a result that needs checking?
If you find a discrepancy, report a problem with CSS Unit Converter. Include a non-sensitive example, the selected options, the result you expected and the result shown. This makes the issue easier to reproduce. See About & privacy for how the site handles tool inputs.