Tablets Per Dose Calculator
Work out how many tablets or capsules make up an ordered dose from the ordered amount and the strength of one tablet, using desired-over-have.
How it works
Tablets = ordered dose ÷ strength per tablet (Desired ÷ Have)
The classic “desired over have” rule turns a written order into a countable number of tablets: divide the dose the prescriber wants by the strength printed on each tablet. A clean whole number is ideal; a fraction is only acceptable when the tablet is scored and the drug tolerates splitting (many extended-release and enteric-coated tablets must never be broken). Use this as an arithmetic check, then verify against the actual stock and the drug’s label.
Worked example
An order for 500 mg where each tablet is 250 mg gives 500 ÷ 250 = 2 tablets. An order for 375 mg with 250 mg tablets gives 375 ÷ 250 = 1.5 tablets, which is only safe if that tablet is scored and splittable.
Frequently asked questions
What if the answer is a fraction like 1.5?
A fraction means the ordered dose is not a whole multiple of the tablet strength. Half a tablet is only acceptable for a scored, immediate-release tablet that the label permits splitting; extended-release, enteric-coated or capsule products generally cannot be divided. When splitting is not allowed, query the order or use a different strength.
Does this work for capsules too?
Yes for counting purposes — enter the strength of one capsule. But capsules almost never split, so a fractional result for a capsule usually signals a wrong strength or an order that needs a different product rather than a partial capsule.
What units should I use?
Use the same unit for the order and the tablet strength — both in milligrams, both in micrograms, and so on. Mixing mg with mcg is a common and dangerous error; convert first (1 mg = 1,000 mcg) so the units match before dividing.
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Educational estimate only — not medical advice, and no substitute for a clinician, pharmacist or the product label. Every dose, rate and volume must be independently verified against the actual drug, order and patient before administration. Do not use this tool to self-treat or to bypass an institution’s double-check policy.