Step 1
Month 0-3
Start 6 kg to target 5.74 kg.
- Daily calories
- 260 kcal
- Recheck
- October 2026
Baseline step. Monitor appetite and weekly weight closely.
APOP Protocol · Hepatic Lipidosis Safety Built-In · Vet-Method
Cat Weight Loss Calculator: Safe Diet Plan & Timeline
Is your cat overweight? Get a personalized safe calorie target, 4-step monthly timeline, weekly weight goals, and food portions with built-in hepatic lipidosis risk warnings.
Safe rate: 0.5-2% body weight per monthNever below 70% of RERStep-based APOP method
APOP Method
4-Step Weight Loss Plan
Step 2
Month 3-6
Start 5.74 kg to target 5.49 kg.
- Daily calories
- 251 kcal
- Recheck
- January 2027
Recalculate calories from the actual weight at this step start.
Step 3
Month 6-9
Start 5.49 kg to target 5.24 kg.
- Daily calories
- 242 kcal
- Recheck
- April 2027
Recalculate calories from the actual weight at this step start.
Step 4
Month 9-12
Start 5.24 kg to target 5 kg.
- Daily calories
- 234 kcal
- Recheck
- July 2027
Recalculate calories from the actual weight at this step start.
Tracking Table
Weekly Target Weight Tracker
| Week | Target kg | Target lbs | Daily kcal | Cumulative loss |
|---|---|---|---|---|
| Week 1 | 5.98 kg | 13.2 lbs | 227 | 0.02 kg |
| Week 2 | 5.96 kg | 13.1 lbs | 227 | 0.04 kg |
| Week 3 | 5.94 kg | 13.1 lbs | 227 | 0.06 kg |
| Week 4 | 5.92 kg | 13.1 lbs | 227 | 0.08 kg |
| Week 5 | 5.9 kg | 13 lbs | 227 | 0.1 kg |
| Week 6 | 5.88 kg | 13 lbs | 227 | 0.12 kg |
| Week 7 | 5.86 kg | 12.9 lbs | 227 | 0.14 kg |
| Week 8 | 5.84 kg | 12.9 lbs | 227 | 0.16 kg |
| Week 9 | 5.82 kg | 12.8 lbs | 227 | 0.18 kg |
| Week 10 | 5.8 kg | 12.8 lbs | 227 | 0.2 kg |
| Week 11 | 5.78 kg | 12.8 lbs | 227 | 0.22 kg |
| Week 12 | 5.76 kg | 12.7 lbs | 227 | 0.24 kg |
| Week 13 | 5.74 kg | 12.7 lbs | 227 | 0.26 kg |
| Week 14 | 5.72 kg | 12.6 lbs | 227 | 0.28 kg |
| Week 15 | 5.7 kg | 12.6 lbs | 227 | 0.3 kg |
| Week 16 | 5.69 kg | 12.5 lbs | 227 | 0.31 kg |
Showing the first 16 weeks. The model caps generated weekly targets at 52 weeks.
BCS Guide
Body Condition Score Guide for Cats
1/9
Severely underweight
Do not start a weight-loss plan.
2/9
Very thin
Needs nutrition and veterinary review.
3/9
Thin
Weight gain may be needed.
4/9
Lean ideal
Usually maintain.
5/9
Ideal
Target body condition.
6/9
Slightly overweight
Measured calorie control can help.
7/9
Overweight
Veterinary supervision recommended.
8/9
Obese
Vet-supervised plan strongly recommended.
9/9
Severely obese
Medical supervision required.
Weight Loss Guide
How to Help a Cat Lose Weight Safely
Is My Cat Overweight?
Use BCS first, not scale weight alone. A BCS of 5/9 is ideal; 6/9 is mildly overweight; 7/9 and above should trigger a careful plan and veterinary input.
How Much Should an Overweight Cat Eat?
Weight-loss calories use ideal weight RER, not current overweight body weight. This avoids feeding excess fat mass while keeping the plan above the safety floor.
Hepatic Lipidosis Danger
Cats can develop fatty liver disease when food drops suddenly or appetite stops. Never feed below 70% of RER, and treat 24-48 hours of food refusal as urgent.
Safe Rate Guide
A conservative plan targets about 1-2% body weight loss per month. Faster loss may look efficient but increases medical risk and often causes rebound hunger.
Monthly Check-Ins
Reweigh every 4-12 weeks. If weight loss is too slow, reduce calories by 5-10%. If it is too fast, increase calories by 5-10%.
Food and Enrichment
Wet food can improve fullness because it is high in water. Puzzle feeders, climbing routes, and short play sessions help preserve muscle and reduce begging.
Related Tools
Build the full weight plan
Cat BMI Calculator
Assess Body Condition Score, estimate body fat, calculate ideal weight, and generate a safe cat weight-management timeline.
Cat Feeding Calculator
Calculate exact wet, dry, or mixed feeding portions by kcal, meal count, age, treats, and cat food label values.
Cat Calorie Calculator
Get daily kcal targets using feline RER and MER formulas adjusted for spay status and activity level.
Cat RER Calculator
Calculate Resting Energy Requirement with the vet-standard 70 x W^0.75 formula, full steps, and MER scenario table.
Safe diet planning
Make weight loss slow enough for a cat's liver
Cat weight loss is not a smaller bowl by guesswork. The useful plan starts with ideal weight, calculates RER from that target body size, keeps calories above a visible safety floor, and turns the goal into weekly weights that can be checked before risk builds.
Result guide
How to read the weight-loss result
The daily calorie target uses ideal-weight RER x 1.0. Treat calories are separated so rewards do not quietly replace meals, and the hepatic lipidosis meter keeps the 70% RER floor visible. The timeline is intentionally gradual because cats need steady intake even while losing fat.
- Use the BCS-based ideal weight unless your veterinarian has provided a target weight.
- Keep treats within the 10% budget and subtract them from meals.
- Treat BCS 7/9 or higher as a vet-supervised plan, not a simple home diet.
- Call a veterinarian immediately if food refusal lasts 24-48 hours.
Ideal-weight RER is the anchor
Using current overweight body weight can overfeed the fat mass. Using ideal-weight RER gives the plan a target body size while staying tied to veterinary energy math.
The floor is not a goal
The 70% RER line is a danger boundary. A plan near that line needs professional review rather than another calorie cut.
Progress is a trend
One weigh-in can be noisy. The weekly tracker is meant to show direction across several weeks, then guide careful 5-10% adjustments.
Diet decisions
Choose the next move from risk and response
The same calorie result can mean different next steps depending on BCS, appetite, current intake, and early weight trend. Use the plan as a measured starting point, then let rechecks decide whether to hold, adjust, or call the veterinarian.
BCS 6/9
Mild overweight cats often respond to measured meals, counted treats, and more play, but the target still needs to be gradual.
Start the calculated portions and weigh weekly for the first month.
BCS 7-9/9
Higher BCS scores carry more medical risk and should be supervised, especially if the cat has diabetes, arthritis, urinary signs, or low activity.
Review the target calories and recheck schedule with a veterinarian before making large cuts.
Appetite drops
Food refusal is not a normal diet response in cats. The safety priority is restoring intake and checking for illness, not continuing the deficit.
Contact a veterinarian immediately if refusal reaches 24-48 hours.
Weekly at home
Weigh weekly during active loss and compare against the tracker rather than reacting daily.
Every 4-12 weeks
Recheck body condition and calories, then adjust by 5-10% when the trend is off target.
Same-day concern
Call a veterinarian for food refusal, rapid loss, lethargy, vomiting, or weakness.
How to run the plan
1
Confirm the starting score
Score BCS, weigh on the same scale, and save the current daily calories before changing portions.
2
Transition gradually
Move toward the calculated daily target over about two to four weeks, especially when the current intake is much higher.
3
Recheck and adjust
Review weight every 4-12 weeks. If loss is too slow or too fast, adjust calories by about 5-10% and keep appetite normal.
FAQ
Frequently Asked Questions About Cat Weight Loss
How do I calculate how many calories my overweight cat should eat?
For weight loss, calculate RER from ideal weight, not current weight: RER = 70 x ideal weight in kg^0.75. The daily weight-loss target is ideal-weight RER x 1.0. Never feed below 70% of RER.
How fast should a cat lose weight safely?
A conservative safe target is about 1-2% of body weight per month. Faster loss can raise hepatic lipidosis risk, especially if appetite drops.
What is hepatic lipidosis?
Hepatic lipidosis is a dangerous fatty liver condition in cats. It can happen when food intake drops suddenly and fat floods the liver. If a cat refuses food for 24-48 hours, contact a veterinarian immediately.
How do I find my cat's ideal weight?
Use Body Condition Score. BCS 5/9 is ideal, and each point above 5 is often treated as roughly 10-15% excess weight. This calculator uses a 12% midpoint estimate.
What is the step-based weight loss method?
The step method divides weight loss into 3-month stages. At each stage, recheck weight and recalculate calories from the current body weight and target path.
Is wet food or dry food better for weight loss?
Wet food is often useful because it is high in water and lower in calorie density. Dry food can work too, but it must be measured carefully because small volume errors can add many calories.