Frequently Asked Questions
Last updated: June 7, 2026
Our calculators use the standard Resting Energy Requirement (RER) and Maintenance Energy Requirement (MER) formulas used by veterinary nutritionists worldwide. The results are accurate estimates based on your inputs. However, every cat is unique — medical conditions, medications, and individual metabolism can affect actual needs. Always use our calculator results as a starting point and confirm with your veterinarian.
No. All calculations happen entirely in your web browser. Your cat's weight, age, and other data never leaves your device. We do not have servers that process or store your inputs. The Weight Tracker uses your browser's localStorage to save data between sessions, but this data stays on your computer and can be cleared at any time.
Yes. Every tool on Cat Calorie Tool is completely free to use. We do not have paywalls, premium tiers, or subscription plans. We may display advertisements to help cover hosting costs, but the tools themselves will always remain free.
While the underlying RER formula is similar for dogs and cats, the MER multipliers and nutritional recommendations differ significantly between species. Our calculators are specifically calibrated for feline physiology. We recommend using dog-specific tools for canine nutrition calculations.
You can use the calculator to get a baseline estimate, but cats with medical conditions (diabetes, kidney disease, hyperthyroidism, etc.) often have significantly different calorie and nutrient needs. Our calculators do not account for disease-specific requirements. Please consult your veterinarian or a board-certified veterinary nutritionist for a therapeutic diet plan.
Each tool that saves data has a "Reset" or "Clear History" button. You can also clear all saved data by clearing your browser's localStorage for catcalorietool.org. In most browsers, go to Settings > Privacy > Clear browsing data > Select "Cookies and site data" for this site only.
All articles are written by Olivia Brennan, a certified veterinary nutritionist with 8 years of clinical experience. She holds a BS in Animal Science from Oregon State University and an MS in Veterinary Nutrition from the University of Illinois. Every article references peer-reviewed veterinary research and is based on her clinical case experience.
Absolutely! We love featuring real cat weight loss journeys from our community. Email your story (with photos if you have them) to privacy@catcalorietool.org. Please include your cat's starting weight, goal weight, the plan you used, and how long it took. We may feature your story on the blog with your permission.
No. We do not endorse, recommend, or partner with any specific pet food brands. Our articles discuss categories and types of food (wet vs. dry, prescription vs. commercial, etc.) based on nutritional science, but we never tell you which brand to buy. We believe cat parents should make informed decisions based on their cat's individual needs and their veterinarian's guidance.
Cats are notoriously stubborn about change. If your cat refuses the new portion, do not panic and immediately revert to the old amount. Instead, reduce the transition speed—cut by only 5% per week instead of 10%. Try warming the food slightly (10 seconds in the microwave) to enhance aroma, or switch to a more palatable wet food temporarily. If your cat eats less than 75% of the recommended calories for more than 48 hours, contact your veterinarian. Prolonged undereating can lead to hepatic lipidosis, especially in overweight cats.