Lesson overview
Medication Math Unit Conversions
Ready when you are
Start with short teaching slides, then answer the lesson questions. Your progress stays on this browser.
Learning outcomes
What you will learn
- convert g ↔ mg ↔ micrograms
- convert L ↔ mL
- convert hours ↔ minutes
- use a supplied kg ↔ lb factor when a question requires it
- predict whether the number should get bigger or smaller
- recognise when a simple unit conversion is not enough
Clinical connection
Why this matters
If the units do not match, the arithmetic that follows can be wrong even when the calculator work is correct. Checking the units first makes later medication calculations much easier to set up.
Quick concept
Convert the unit without changing the amount
Medication unit conversion changes how the same quantity is expressed. First name the starting unit and the target unit, then use the correct relationship and check whether the number should become larger or smaller. Only convert between compatible quantities: mg cannot become mL unless a concentration links mass and volume.
Formula
1 g = 1000 mg; 1 mg = 1000 mcg; 1 L = 1000 mL; 1 hr = 60 min
Worked example
Educational example: convert 0.25 g to mg.
0.25 g × 1000 mg/g = 250 mg
Answer: 250 mg
Keep the value and unit together throughout the calculation and use safe decimal notation. Do not treat unlike units such as mg and mL as directly interchangeable without the missing relationship, such as a supplied concentration.
Lesson plan
How the lesson works
- 1
Learn
Short teaching slides explain one idea at a time with plain-language examples.
- 2
Practise
Answer calculation or scenario questions and receive immediate feedback.
- 3
Finish
Complete the lesson check and save your learning progress on this browser.
Keep going
Learn, practise, apply and check this skill
Use the page that matches what you need next. Each resource has a different job, so the lesson can stay focused on teaching the skill.
Practise
Medication unit conversion practice
Practise g, mg, mcg, L, mL, time and source-supplied lb-to-kg conversions across four levels.
Understand
Medication maths unit conversions guide
Review conversion direction, unit matching, safe notation and common medication-maths errors.
Check
Scientific Calculator
Check arithmetic after you have chosen the correct conversion relationship and target unit.
Apply
Medication & IV Safety cases
Use unit conversions as part of realistic medication and IV calculation workflows.