Calorie Deficit & Macro Calculator

What this is

Fat loss isn’t one-size-fits-all. Many women do lose fat best in a controlled calorie deficit — a deliberate, not-too-large gap below the calories they burn (their TDEE). But plenty of women shouldn’t be dieting at all. If you’ve spent years under-eating or chronically dieting, you’re under heavy stress, you’re peri- or post-menopausal with stalled energy, you’re recovering from disordered eating, or you’re already quite lean, a deficit often backfires — costing muscle, draining energy, and setting up the rebound. For those women, eating at maintenance while building muscle is what finally changes body composition. This tool lets you set your target either way, then splits the result into protein, fat, and carbs — with protein set high to protect lean mass. Muscle is medicine.

Not sure which woman you are? That’s exactly what my book, Your Metabolic Reboot, is built to help you figure out — so you stop guessing and start eating in the way your physiology actually needs.

How to use it

1. Enter your TDEE (from the TDEE calculator), your sex, height, and current weight.
2. Choose your target. Maintenance if you’re recovering, stressed, peri/post-menopausal with low energy, or already lean. Gentle (~10%) or Moderate (~20%) if a controlled deficit is right for you.
3. Press Calculate for your daily calorie target, projected weekly fat loss, and macro split.
4. Prioritize hitting protein every day; let fat and carbs flex around your preferences and training.

How the numbers are set

Protein is the number to hit: roughly 1 gram per pound of your adjusted body weight, which scales it to your frame without over-counting excess fat mass — this is what protects muscle, especially on GLP-1 medications. Fat and carbs are more of a range than a fixed target, so this calculator simply picks sensible values within healthy bounds and lets you adjust from there. Fat is kept from dropping below about 0.45 g per pound of your adjusted body weight, because fat that runs too low can disrupt your hormones. Whatever calories remain after protein and fat go to carbs — and there’s real room to flex here: many women feel and train better with more carbs on training days, while pushing carbs too low can leave you tired, flat, and mentally foggy. So treat the fat and carb numbers as a sensible starting split you can shift around your training and how you feel, and keep protein as your anchor. Ideal and adjusted body weight come from the Devine formula using your height and sex; projected fat loss assumes roughly 3,500 calories per pound of fat.

Limitations & the honest fine print

• Predicted loss is an average, not a promise. Water, hormones, sodium, and your cycle move the scale day to day. Judge progress over 2–3 weeks, not overnight.
• Don’t starve. Going far below your needs backfires. As a general floor, most women shouldn’t drop below ~1,200 cal/day without medical supervision — this tool will flag it if your target gets that low.
• A deficit isn’t always the answer. If you’re under-recovered, highly stressed, or have a long dieting history, maintenance plus strength training is often the faster path. Your Metabolic Reboot walks you through deciding.
• Macros are a framework, not a religion. Consistency with protein and overall calories drives 90% of results.
• On a GLP-1, thyroid medication, or with a long dieting history? Your needs may differ — this is exactly where individualized, tested plans beat any calculator.
• Educational only — not medical or nutrition advice.