Tablet dosing
Enter the prescribed dose and the strength in one tablet. MedMaths can match mcg, mg, or g before dividing.
Use the dose on the order or in the study question.
Use the strength printed for one tablet, not the total amount in the pack.
Match the prescribed dose to the tablet strength
Educational medication-maths support only. Confirm the order, patient weight when used, dose frequency, maximum-dose limits, exact product, formulation, splitting suitability, and local policy before administration.
How many tablets? Divide the dose ordered by the strength of one tablet. If 500 mg is ordered and each tablet is 250 mg, that's 500 ÷ 250 = 2 tablets. Make sure both numbers are in the same unit first, and always check the order and the label before you give anything.
Tablets, pills and capsules are worked out the same way: dose ordered ÷ strength of each unit.
Simple answer
Convert the prescribed dose and one-tablet strength to the same mass unit, then divide the dose by the strength.
This is the same arithmetic as D/H × Q when Q is 1 tablet. For weight-based orders, use kilograms and preserve whether the order is mg/kg per dose or mg/kg/day before dividing the per-dose amount by the tablet strength.
Calculate the exact tablet amount from a fixed prescribed dose or a weight-based order. MedMaths matches mcg, mg, and g strengths, accepts kg or lb for weight-based calculations, and keeps the arithmetic separate from product-specific splitting or formulation decisions.
Clinical use and safety
The arithmetic can be correct while the clinical decision is still wrong. These boundaries show what the calculator can and cannot establish.
Formula logic and known-value examples are checked as part of the MedMaths review process.
See how MedMaths checks calculator methods →Review fixed-dose and weight-based formulas, unit matching, worked examples, tablet-splitting checks, and focused FAQs.
Tablets = matched dose ÷ matched one-tablet strength
If the units differ, convert mcg, mg, or g first. Example: 0.125 mg = 125 mcg; 125 ÷ 62.5 = 2 tablets.
If the same prescribed dose is supplied as a liquid rather than a tablet, use the mg to mL Calculator.
Prefer another setup method? The Medication Calculation Methods Guide compares D/H × Q, ratio and proportion, and dimensional analysis without changing the underlying dose relationship.
Per dose = weight (kg) × mg/kg per dose
For mg/kg/day: daily mg ÷ prescribed doses/day
Tablets = per-dose mg ÷ matched tablet strength
The calculator accepts kg or lb but always shows the kilograms used in the medication calculation.
For a weight-based order supplied as a liquid, use the mg/kg to mL Calculator instead.
Confirm whether the order is a fixed dose, mg/kg per dose, or mg/kg/day. Keep the dose basis exactly as prescribed.
Use the amount in one tablet, not the total amount in the packet, bottle, or blister strip.
A fractional tablet amount is a mathematical result only. Do not infer that the exact product can be split, and do not round an awkward result automatically.
Convert mcg, mg, or g so the prescribed dose and one-tablet strength use the same mass unit before dividing.
Use the amount contained in one tablet. The number of tablets in the packet or blister strip is not the dose on hand.
A daily weight-based amount must be divided by the prescribed number of doses before converting the per-dose amount into tablets.
Keep the exact arithmetic result. Product-specific splitting, available strengths, and local medication policy determine whether that dose can actually be supplied.
500 mg ÷ 250 mg/tablet
2 tablets
1 g = 1,000 mg; 1,000 mg ÷ 500 mg/tablet
2 tablets
20 kg × 10 mg/kg/dose = 200 mg; 200 mg ÷ 100 mg/tablet
2 tablets
The calculator shows exact arithmetic. It does not decide whether a tablet can be split, crushed, dispersed, or substituted with another formulation.
A mathematical fraction does not prove the tablet may be split. Whether a specific tablet can be split or otherwise altered depends on the exact product and formulation — not the dose arithmetic. FDA advises that approved splitting information is provided in the product labelling when splitting has been evaluated. Modified-release, enteric-coated and other specialised products require formulation-specific checks.
Confirm the approved product information or prescribing information, pharmacist or prescriber instructions, and local medication policy before splitting, crushing or otherwise altering a tablet.
The calculator is kept answer-first. Step-by-step practice, tablet-label reading, and lesson-check questions live in the dedicated Learn lesson.
It depends on the strength of each tablet. 500 mg is 1 tablet of 500 mg, 2 tablets of 250 mg or 10 tablets of 50 mg.
Convert the prescribed dose and tablet strength to the same mass unit, then divide the prescribed dose by the amount in one tablet. For example, 500 mg ordered and 250 mg/tablet gives 2 tablets.
D/H × Q means desired dose divided by the dose on hand, multiplied by the quantity that contains the on-hand dose. For a tablet labelled with its strength per 1 tablet, Q is 1 tablet, so the arithmetic simplifies to prescribed dose ÷ tablet strength = number of tablets.
Yes. Convert mcg, mg, or g to the same mass unit before dividing. This calculator performs that unit matching transparently and shows the converted values in the working when needed.
For mg/kg per dose, multiply the dose by the patient weight in kilograms to obtain mg per dose, then divide by the tablet strength. For mg/kg/day, first calculate the total daily mg and divide it by the prescribed number of doses per day before converting to tablets.
mg/kg per dose calculates each dose directly from body weight. mg/kg/day calculates the total amount for the whole day, which must then be divided by the prescribed number of doses. They are not interchangeable.
Yes. The calculator accepts kg or lb. Pounds are converted to kilograms before the weight-based medication calculation, and the exact kilogram weight used is shown in the result.
Yes. A value such as 1.5 tablets can be the exact mathematical result. It does not prove that the exact product can be split or that the calculated fraction is an approved administration amount.
Keep 1.3 tablets as the exact arithmetic result and do not automatically round it to a convenient whole, half, or quarter tablet. Check the order, available strength, exact product information, pharmacist advice, and local policy.
No. Tablet splitting is product specific. FDA notes that approved splitting information appears in the product labelling when it has been evaluated, and many modified-release or otherwise unsuitable products should not be split.
Do not choose a rounding direction simply to make the number convenient. Any rounding, splitting, or formulation change should follow the prescription, available strengths, product information, pharmacist advice, and local medication policy.
When the prescribed dose and tablet strength use the same mass unit, divide the prescribed dose by the strength in one tablet. This is equivalent to D/H × Q when Q is 1 tablet. Ratio and proportion or dimensional analysis can arrange the same medication relationship in a different way.
Use this calculator when the medicine is supplied as a tablet with a known strength per tablet. The word pill is informal and can also refer to capsules or other oral dosage forms, so confirm the actual formulation before using tablet arithmetic.
Unlike a named clinical equation such as Cockcroft-Gault or Mosteller BSA, this calculator uses standard arithmetic or unit relationships rather than a formula that MedMaths can reliably trace to one historical researcher or publication. MedMaths therefore identifies who wrote and reviewed the page instead of assigning a historical formula author.
The calculation rearranges verified dose, strength, concentration, quantity, weight, or unit values into the amount requested. It does not decide whether a medicine, dose, route, formulation, maximum dose, or patient-specific plan is clinically appropriate.
This calculator uses standard oral medication dose arithmetic. It is not attributed to a named researcher.
Supporting references
Safety and quality guidance
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