Wellness

Instant, private, and free

Medication Dosage Calculator.

Calculate safe medication dosages by age, weight, and renal function using Clark's Rule, BSA, or Young's Rule

On-device calculationNo signup
01

Set your values

Results update as you type.

⚠️ Medical Disclaimer

This calculator is for educational purposes only. Always verify calculations with a pharmacist or physician. Dosages may vary based on medication-specific guidelines, renal/hepatic function, and drug interactions.

70.0kg
2200
170.0cm
50250
35.0years
0120
Age Group
500.0mg
105000
3.0times/day
18
Calculation Method

Single Dose

500mg

clark method (adult)

Daily Total

1500mg

3x daily (1500 total)

Educational formula example only — use a medication-specific prescription and confirm all dosing with a clinician or pharmacist.

FAQs

What is Clark's Rule?

Clark's Rule is the most common method for calculating pediatric dosages: Child dose = (Child weight in kg ÷ 70) × Adult dose. Based on a 70 kg average adult.

When should renal function be considered?

Renal function (eGFR) adjustment is important for medications cleared by the kidneys. Ask your pharmacist if your medication requires adjustment.

Is this calculator accurate for all medications?

No. Dosages vary significantly by medication type and individual factors. Always verify with a pharmacist or physician.

Authoritative Source & Methodology
Reviewed: 2026-07-15

Source: FDA Drug Dosing Guidelines & Pediatric Weight-Based Rules (US / International)

Reviewer: Mathify content team

Notice: Dosing estimates do not replace a physician or pharmacist prescription. Always verify with official drug package inserts.