What This Calculator Does
The Cephalexin For Dogs Dosage Calculator estimates how many milligrams of cephalexin a dog should receive per dose based on its body weight. Cephalexin (a first-generation cephalosporin antibiotic) is commonly prescribed by veterinarians for skin, soft tissue, urinary, and respiratory infections in dogs. A frequently cited reference rate is about 22 mg per kilogram of body weight given every 12 hours, though your vet may use anywhere from 15 to 30 mg/kg depending on the infection.
How To Use It
Enter your dog's weight and choose kilograms or pounds. The default mg/kg rate is set to 22, but you can change it to match your veterinarian's prescription. Pick how many times per day the medication is given. The calculator shows the milligrams per dose, the total daily milligrams, and the weight converted to kilograms.
The Formula Explained
The core equation is simply $$\text{Dose (mg)} = \text{Weight (kg)} \times \text{mg/kg rate}$$ If your weight is in pounds, it is first converted using \(1\ \text{kg} = 2.2046\ \text{lb}\). The total daily dose multiplies the single dose by the number of administrations per day.
Worked Example
A 20 kg dog at 22 mg/kg: $$20 \times 22 = 440\ \text{mg per dose}$$ Given twice daily, the total is \(440 \times 2 = 880\) mg per day. The medication would then be matched to the nearest available capsule or tablet strength (e.g. 250 mg or 500 mg) by the vet.
FAQ
Is this a substitute for veterinary advice? No. This tool gives a rough estimate. Dosage, frequency, and duration must be set by a licensed veterinarian.
What is the usual cephalexin dose for dogs? Commonly 15–30 mg/kg every 8–12 hours; 22 mg/kg every 12 hours is a typical midpoint.
Can I round to the nearest pill? Your vet will round to a practical capsule strength — never adjust the dose yourself without guidance.
