Bravecto Dosage Calculator for Dogs

What Is the Bravecto Dosage Calculator for Dogs?

The Bravecto Dosage Calculator for Dogs works out the exact fluralaner dose for both Bravecto products, the standard 12-Week Chew and the separate, lower-strength 1-Month Chew, directly from the FDA-approved product label published by Merck Animal Health. Enter your dog's exact current weight and the calculator matches it to the correct FDA weight band, shows both products' charts side by side for comparison, and automatically calculates the next dose due date based on the product's dosing interval. Most existing Bravecto dosage references online show only a static chart for one product at a time, leaving pet owners to manually cross-check which chart applies when switching between the 12-Week and 1-Month formulations, a mix-up this calculator is built specifically to prevent.

Fluralaner, the active ingredient in Bravecto, is an isoxazoline-class parasiticide that kills fleas and ticks, and correct weight-based dosing matters because the margin between an effective dose and a higher-than-recommended one is part of standard veterinary safety guidance for this drug class. Working from the dog's verified current weight, rather than an estimate or an outdated weigh-in, is the single most important step in using this medication correctly.

How the FDA Weight Bands and Dose Strengths Work

The Bravecto 12-Week Chew is labeled to deliver a minimum of 25 mg/kg (11.4 mg/lb) of fluralaner, supplied in five fixed chew strengths: 112.5 mg for 4.4 to 9.9 lb dogs, 250 mg for 9.9 to 22 lb dogs, 500 mg for 22 to 44 lb dogs, 1000 mg for 44 to 88 lb dogs, and 1400 mg for 88 to 123 lb dogs. The Bravecto 1-Month Chew instead delivers a minimum of 10 mg/kg (4.5 mg/lb), using a separate set of five chew strengths, 45 mg, 100 mg, 200 mg, 400 mg, and 560 mg, across the same five weight bands. Because the milligram strengths differ so significantly between the two products at an identical dog weight, this calculator displays both charts together specifically so a pet owner switching products, or confirming a refill, can see at a glance that a chew from one product does not substitute for the other.

Why Exact Current Weight Matters More Than the Box Size

Bravecto chews are manufactured at fixed strengths and are not designed to be split or adjusted, so the entire dosing decision rests on matching the dog's true current weight to the correct band. The product label and veterinary guidance are consistent on this point: using an estimated, remembered, or outdated weight instead of a recent, accurate weigh-in is one of the most common preventable dosing errors with this medication, and even a small mismatch can shift a dog into a band that under-protects or over-doses them relative to their actual size.

Dosing Interval and Special Cases

The 12-Week Chew is dosed once every 12 weeks, or every 8 weeks specifically where exposure to the Lone Star tick is a concern, while the 1-Month Chew is dosed every 30 days. The label has not been evaluated in puppies younger than 6 months or under 4.4 lb body weight, and dogs heavier than 123 lb require a veterinarian-determined combination of chews rather than a single dose from the standard chart. If you also track other medication dosing for your dog by exact weight, our Dog Dosage Calculator applies the same weight-based approach to other common veterinary medications.

Accuracy and Limitations

The weight bands and milligram doses in this calculator are taken directly from the current FDA-approved Bravecto label, but a calculator cannot account for a dog's individual health history, current medications, or breed-specific sensitivities, all of which a veterinarian should review before any dose is given. Isoxazoline-class products including Bravecto carry an FDA-required note regarding rare neurologic adverse events such as seizures, ataxia, and muscle tremors, particularly relevant for dogs with a prior seizure history, a consideration this calculator cannot evaluate and a vet visit can.

The Most Common Bravecto Dosing Mistake

The mistake I see most often is a pet owner reusing the weight band from a previous Bravecto product when switching between the 12-Week and 1-Month chews, assuming the bands and box colors line up the same way across both. They frequently do not match the dog's actual current weight if any time has passed since the last accurate weigh-in, and the two products' milligram strengths differ enough at the same band that an incorrect carryover assumption can mean roughly double or half the intended dose. Before giving any refill, especially after switching products or after any noticeable weight change, I confirm the dog's current weight against the specific product's own chart rather than relying on memory of a previous box.