Keto + intermittent fasting calculator

Build a practical keto + intermittent fasting plan that matches your goal, experience, stress level, sleep quality, and daily rhythm. The calculator suggests a fasting schedule, calories, keto macros, meal timing, and electrolyte guidance in one place.

When this calculator is most useful

•If you want more than a generic 16:8 plan and need a schedule matched to real life.
•If you want keto macros adjusted to a shorter eating window.
•If stress or poor sleep make aggressive fasting feel too hard.
•If you want to place meals earlier in the day instead of eating too late.
•If you want a gentler fasting plan before moving to longer fasts.
•If you want one result that combines IF timing, keto macros, and meal spacing.

Result What result means Tips FAQ

Enter your details

We use your body data, daily routine, recovery, and fasting experience to suggest a keto-friendly fasting window and a simpler eating plan.

System

ModeAdds an intermittent fasting schedule on top of keto macros and meal timing.

Personal

Sex

Age

years

Weight

Height

Lifestyle

Activity levelRegular movement or 3-4 workouts most weeks.GoalUses a moderate calorie deficit and allows longer fasting if recovery is good.Stress levelSome pressure is present, so we avoid jumping too aggressively.SleepSleep is inconsistent, so the plan stays moderate.

Fasting experience

IF experienceNew to fasting or only tried short overnight fasts.Current eating patternA regular breakfast, lunch, and dinner rhythm.

Schedule

Wake-up timeBedtime

Your keto + fasting plan

A practical plan based on your goal, recovery, and daily routine.

12:12

Recommended mode

08:30-20:30

Eating window

12 h

2,227 kcal

Daily calories

20 g

Net carbs target

12:12

Day timeline

Your eating window starts 1-2 hours after waking and ends about 3 hours before bed to avoid late eating.

Wake: 07:30 Sleep: 23:00

Fasting

20:30-08:30

Eating

08:30-20:30

IF plan

Fasting window

12:12

Eating window

08:30-20:30

Estimated sleep

8.5 h

Meals in window

Macros for the eating window

Protein stays supportive, carbs stay low enough for keto, and fat fills the remaining calories.

125 g

Protein

183 g

Fat

20 g

Carbs

Meal timing

Use these meal times as a simple starting point inside your eating window.

Meal 1

08:30

Macro split: 30%

Meal 2

12:30

Macro split: 30%

Meal 3

16:00

Macro split: 40%

Electrolytes during fasting

During fasting you may need more electrolytes, especially sodium. This matters even more on keto because lower carbs often increase fluid and sodium loss.

Sodium target

3,000-5,000 mg

Smart hints

Start with 12:12 or 14:10 if you are new. A plan you can repeat is better than an aggressive plan you quit.

What to do next

Use nearby calculators to make the plan easier to follow

Review your keto macro plan

Track how timing affects your GKI

Check your electrolyte target

Balance your water intake

What the result means

How the calculator builds your plan

Calories start with BMR and TDEE, then adjust by goal. Fat loss uses a moderate deficit, maintenance stays near baseline, and metabolic health stays gentler.

Protein is set at about 1.6 g per kg of body weight, carbs stay low for keto, and fat fills the remaining calories.

The fasting plan starts from your experience level, then gets softened if stress is high or sleep is poor.

The eating window is placed inside your active day so you can eat earlier, not right before sleep.

Meal timing is simplified into 2-3 meals so the plan feels practical instead of rigid.

Practical tips

Small practical steps to help you apply the result day to day.

If you are new, hold the same schedule for 10-14 days before deciding it is too easy or too hard.

Keep the first meal protein-forward so the eating window feels steadier and more satisfying.

Do not chase longer fasts when stress is high, workouts are intense, or sleep is already poor.

Earlier dinners usually make the next morning easier than late-night eating.

Recalculate after a noticeable weight change or when your daily routine shifts.

Add water and electrolytes during fasting, especially in the first weeks of keto.

FAQ

Short answers to common questions about calculations and interpretation.

Is a longer fast always better for fat loss?

No. A longer fast only helps if you recover well and can repeat it consistently. High stress and poor sleep often make shorter fasts a better choice.

Why did the calculator recommend 12:12 or 14:10 instead of 16:8?

That usually happens when you are new, your stress is high, or sleep is poor. The plan intentionally starts softer so it is easier to sustain.

Why are macros still important if I use intermittent fasting?

Fasting changes timing, but keto still depends on calories, protein, fat, and carbs. The eating window works best when those numbers are still reasonable.

Can I move the eating window later?

You can, but earlier eating usually works better for appetite, energy, and sleep. The calculator intentionally avoids very late eating.

How many meals should I eat in the window?

Most people do best with 2-3 meals. Very short windows may work with 1-2 meals, but that is usually better for experienced fasters.

This calculator is for educational purposes only and does not replace medical advice. If you have a medical condition, take medication, or have a history of eating disorders, review fasting changes with a qualified clinician.

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