Unit Converters
Length Converter
Result = Value × (From ÷ To)
Convert between cm, m, mm, in, ft for charting height or measuring wound dimensions.
Convert Length →Mass & Weight Converter
Result = Value × (From ÷ To)
Convert between kg, g, lb, oz for reconciling self-reported weight against metric dosing.
Convert Mass →Volume Converter
Result = Value × (From ÷ To)
Convert between mL, L, fl oz, tsp, tbsp for medication teaching and OTC label reconciliation.
Convert Volume →The unit converters handle the everyday US-vs-metric conversions that show up in clinical practice: height between cm and inches, weight between kg and pounds, volume between mL, ounces, teaspoons, and tablespoons. Each converter shows the substituted arithmetic so the student can see the conversion factor in action.
These are deliberately separate from the dosage calculators above so you can use them stand-alone — for example, converting a patient-reported weight in pounds to kilograms before plugging it into a weight-based dosing calculator.
When to use these calculators
Length conversion is most useful for charting patient height when the reported number is in inches but the EMR or formula expects cm. The body surface area (BSA) calculator on this site, for example, expects height in cm and weight in kg — these converters bridge the patient-facing US units to the calculation-facing metric units.
Mass and volume conversions show up most often in patient teaching: explaining a 5-mL dose as 'a teaspoonful,' converting an OTC bottle's fluid ounces to mL, or reconciling a self-reported weight in pounds against a metric prescription dose. The converters are scoped to clinically useful unit pairs rather than every possible engineering unit.
Frequently Asked Questions
- Why not just use my phone's calculator?
- You can — these converters add value mainly in the 'show your work' display. The substituted arithmetic surfaces the conversion factor (e.g., 2.205 lb per kg), which helps students learn the factor and helps clinicians spot a wrong-direction conversion (multiplying instead of dividing) before it causes a drug-dose error.
- How precise are the conversion factors?
- The factors are exact where the relationship is exact (1 lb = 0.45359237 kg, by definition) and rounded to a reasonable number of decimal places where the calculation result wouldn't benefit from more precision (clinical doses are not measured to the microgram for unit conversion purposes). [REVIEW: confirm precision is appropriate for your use case].
- Does the converter handle US vs Imperial unit differences?
- The volume converter assumes US fluid ounces, US teaspoons, and US tablespoons by default — the units used in clinical practice in the United States. Imperial (UK) fluid ounces are slightly different (28.4 mL vs 29.6 mL for the US) but not surfaced as a separate option in the current build. [REVIEW: confirm scope].
- Why are these grouped under 'Unit Converters' instead of integrated into the calculators?
- Calculator inputs accept the canonical units directly (e.g., the BSA calculator takes cm and kg). The unit converters exist for the conversion step the user does mentally beforehand. Keeping them as separate calculators makes them findable as standalone tools when the user only needs the conversion.