What this calculator does
The Omega-3 For Dogs Calculator estimates a sensible daily target for combined EPA and DHA — the two key long-chain omega-3 fatty acids found in fish oil. Instead of dosing simply by body weight (linear), it scales by metabolic body weight, which is body weight raised to the power of 0.75. Metabolic scaling reflects how energy and nutrient needs grow more slowly than size, so a 40 kg dog does not need twice the dose of a 20 kg dog.
How to use it
Enter your dog's current weight and choose kilograms or pounds. The calculator converts pounds to kilograms automatically, then returns the recommended combined EPA + DHA in milligrams per day. Compare this number to the EPA + DHA content listed on your fish oil or supplement label (not the total fish oil amount, which includes other fats).
The formula explained
The core equation is $$\text{mg} = 75 \times \text{weight(kg)}^{0.75}$$ The 0.75 exponent is the standard allometric scaling factor. For example, a 20 kg dog: \(20^{0.75} \approx 9.457\), so \(75 \times 9.457 \approx 709\) mg of combined EPA + DHA per day. A 30 kg dog works out to roughly 962 mg per day — higher in total, but lower per kilogram, as metabolic scaling predicts.
FAQ
Is this a substitute for veterinary advice? No. This is a general wellness estimate. Dogs with specific conditions (arthritis, kidney disease, skin allergies, heart disease) may need different therapeutic doses, so confirm with your veterinarian.
EPA + DHA or total fish oil? Use the EPA + DHA value, not total fish oil. A "1000 mg fish oil" capsule often contains only 300 mg of EPA + DHA, so read the label carefully.
Can I give too much? Yes. Very high doses can affect blood clotting and cause loose stools. Start low and increase gradually, and avoid exceeding your vet's recommended ceiling.
