Calculator panic
Any calculator is provided by the center or built into the exam software. Practicing without your own device, and knowing the conversions as recall, removes almost all of the difficulty.
A specific, common and entirely fixable anxiety.
What you actually get
You do not bring your own calculator. Where one is available it is provided by the test center or built into the exam software, and the current candidate rules govern which.
Check the rules close to your date, because they change.
Why that unsettles people
Not the arithmetic. The unfamiliarity. A candidate who has done every practice calculation on their own phone or handheld has built fluency with an interface they cannot take in.
Practice without your own device from the first week. Do the arithmetic on paper where you can, and where you use a calculator, use a plain one you have no muscle memory for. Then the interface on the day is no worse than the one you trained on.
What should never need a calculator
The conversions. Five mL to a teaspoon, 15 to a tablespoon, 30 to a fluid ounce, 2.2 pounds to a kilogram, a percentage times ten for mg per mL.
These should arrive as recall. Any of them you reach for a calculator to do is costing you seconds you need elsewhere.
Estimate first, always
Before calculating, decide roughly what the answer should be. A 20 kg child is getting single-digit millilitres of a suspension, not hundreds.
That habit catches the decimal-place error, which is the mistake most likely to turn a correct method into a wrong answer, and it works whatever calculator you are given.
Show the units
Write the working with units attached at each step, on whatever the center provides. Carrying units through catches an inverted conversion before you pick an option.
And if the calculation will not come
Flag it and move. It is worth one mark, the same as a recall question you could answer in twenty seconds, and there is no penalty for coming back to it later or guessing at the end.
Common questions
Can I bring my own calculator to the PTCB exam?
No. Any calculator is provided by the center or built into the exam software.
How do I prepare for that?
Practice without your own device from week one, so the interface on the day is familiar territory.
What should not need a calculator at all?
The conversions. They should be recall.
How do I avoid decimal errors?
Estimate the answer before calculating, and write units at every step.
What if a calculation will not resolve?
Flag it and move. It is worth one mark and there is no penalty for guessing.