Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
Amount per dose
1.00
mL, or tablets rounded to the nearest quarter
Milligrams per dose
49.90
Total mg per day
99.79
Total units for the course
19.96
Weight in kg
9.98
Psst — share this and help Rex grow
One click, a permanent link with your numbers baked in.
How to use this
- 1Enter pet weight (lb).
- 2Enter prescribed dose (mg/kg).
- 3Enter medication form.
- 4Enter concentration or tablet strength.
- 5Enter doses per day.
- 6Enter days of treatment.
- 7Read your amount per dose on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
Weight-based dosing is where home medication errors happen, especially converting pounds to kilograms and milligrams to milliliters of a suspension. This calculator does both conversions and shows the daily total. Always confirm the dose with your veterinarian.
Worked example
Using the values the calculator loads with:
Inputs
- Pet weight: 22 lb
- Prescribed dose: 5 mg/kg
- Medication form: Liquid suspension (mg/mL)
- Concentration or tablet strength: 50
- Doses per day: 2
- Days of treatment: 10
Results
- Amount per dose: 1
- Milligrams per dose: 49.9
- Total mg per day: 99.79
- Total units for the course: 19.96
- Weight in kg: 9.98
What each field means
Inputs
- Pet weight (lb)
- The pet weight used in the calculation, measured in lb. Starts at 22 lb so you have a working example on load.
- Prescribed dose (mg/kg)
- The prescribed dose used in the calculation, measured in mg/kg. Starts at 5 mg/kg so you have a working example on load.
- Medication form
- Pick the option that matches your situation — the maths changes per option. Choices: Liquid suspension (mg/mL), Tablet (mg per tablet).
- Concentration or tablet strength
- The concentration or tablet strength used in the calculation. Starts at 50 so you have a working example on load.
- Doses per day
- The doses per day used in the calculation. Starts at 2 so you have a working example on load. Accepted range: 1–6.
- Days of treatment
- The days of treatment used in the calculation. Starts at 10 so you have a working example on load.
Results
- Amount per dose
- mL, or tablets rounded to the nearest quarter
- Milligrams per dose
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total mg per day
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total units for the course
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Weight in kg
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Can I split any tablet?
No. Extended-release and enteric-coated tablets lose their release profile when split, and some drugs are hazardous to handle. Ask the pharmacy for a scored strength or a compounded liquid instead.
Is this a substitute for veterinary advice?
It is not. Use it to double-check a dose your veterinarian already prescribed — never to select a drug or dose yourself, and never to give human medications to pets.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Pet Medication Dosage Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/pet-medication-dose
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/pet-medication-dose" target="_blank" rel="noopener">Pet Medication Dosage Calculator — RevenueLab</a> (2026).</p>
Source: [Pet Medication Dosage Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/pet-medication-dose) (2026).