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CalcChef

Protein Timing Window Calculator

Spread a daily protein target over 2 to 8 meals for grams per meal and clock times: 120 g in 4 meals 3 hours apart is 30 g each, 7 AM to 4 PM. How it works

Use the Protein Timing Window Calculator

Range: 20–500g. Only know your body weight? Get a daily total from the Protein Calculator or the Protein Intake Estimator.

Range: 2–8 meals

The ISSN suggests 20 to 40 g per meal

Meals are placed exactly this far apart (1 to 6 hours); the ISSN suggests 3 to 4 hours

Even split
4 meals @ 30g each
Timing Feasible · Total gap 9h

Total Daily:120g
Meals:4
Per Meal:30g
Meals Needed at 30g:4
Waking Time After Last Meal:7h

Meal Schedule

7:00 AM30g
10:00 AM30g
1:00 PM30g
4:00 PM30g

About the Protein Timing Window Calculator

120 g of protein over 4 meals placed 3 hours apart is 30 g a meal at 7:00 AM, 10:00 AM, 1:00 PM and 4:00 PM. The calculator shares the daily total equally between the meals, puts the first one at 7:00 AM and each next one the gap you choose later. For comparison, the ISSN position stand suggests about 0.25 g per kg of body weight, or 20 to 40 g, per dose, spread evenly every 3 to 4 hours.

Grams of protein per meal, by daily total and number of meals

Daily total3 meals4 meals5 meals6 meals
80 g26.7 g20 g16 g13.3 g
100 g33.3 g25 g20 g16.7 g
120 g40 g30 g24 g20 g
150 g50 g37.5 g30 g25 g
180 g60 g45 g36 g30 g

The daily total divided by the number of meals, to one decimal, as the calculator shows it.

Meal times for five meals, by gap

GapMeal 1Meal 2Meal 3Meal 4Meal 5
3 hours7:00 AM10:00 AM1:00 PM4:00 PM7:00 PM
3.5 hours7:00 AM10:30 AM2:00 PM5:30 PM9:00 PM
4 hours7:00 AM11:00 AM3:00 PM7:00 PM11:00 PM

The first meal is always at 7:00 AM. Five meals 4 hours apart use the whole 16-hour waking day the calculator allows.

Frequently asked questions

How much protein should I eat per meal?
The ISSN suggests about 0.25 g per kg of body weight, or 20 to 40 g, per dose, and says older adults likely need about 40 g. At 80 kg, 0.25 g per kg is 20 g. The calculator warns when the even split, or the per-meal target you type, is above 40 g.
How many meals do I need to hit my protein goal?
The summary shows meals needed = daily total ÷ per-meal target, rounded up. 150 g at 30 g a meal needs 5 meals; with 4 meals each one carries 37.5 g and the page says to add meals to stay at the target.
Is 40 g the most protein the body can use at once?
Not according to the ISSN position stand, which sets no cap. It notes that about 70 g appears to be needed to reduce muscle protein breakdown, and that 40 g gave a larger muscle protein synthesis response than 20 g in one study. The 40 g warning here marks the top of the suggested 20 to 40 g range.
Does it plan protein around a workout?
No. There is no input for training time and the first meal is always at 7:00 AM, so the times are an even spacing through the day. If you train at 6:00 PM, move the nearest meal yourself.
Should I have protein before bed?
The ISSN position stand says 30 to 40 g of casein before sleep increases overnight muscle protein synthesis. With 5 meals 4 hours apart the calculator puts the last one at 11:00 PM, the end of its 16-hour day.

Spacing protein across the day

Enter a daily protein target, the number of meals, a per-meal target and the gap you want between meals. The tool shares the total evenly, lays the meals out from 7:00 AM at that gap and checks that they fit a 16-hour waking day. The start time is fixed and there is no input for training, so the result is an even spacing through the day, not a post-workout window.

With 120 g, 4 meals, 30 g per meal and a 3-hour gap, the meals land at 7:00 AM, 10:00 AM, 1:00 PM and 4:00 PM at 30 g each; the gaps total 9 hours, the plan is feasible and 7 waking hours remain after the last meal. At 150 g the same four meals carry 37.5 g each, and 5 meals would be needed to stay at 30 g. A 2.5-hour gap gives 7:00 AM, 9:30 AM, 12:00 PM and 2:30 PM, and times are rounded to the minute. Five meals 4 hours apart fill exactly 16 hours and end at 11:00 PM; six need 20 hours, get a warning, and only the five times before midnight are listed.

How the schedule is built

total gap = (meals − 1) × gap, feasible at 16 hours or less; meal n (counting from 0) falls at 7:00 + n × gap.

Each meal shows daily total ÷ meals, to one decimal: 120 g over 5 meals is 24 g and 150 g over 4 is 37.5 g. The summary also gives meals needed = ceil(daily total ÷ per-meal target), so 150 g at 30 g needs 5 meals, and "Waking Time After Last Meal", 16 hours minus the total gap, never below 0. The per-meal target does not change what each meal shows; it sets the meals-needed figure and a note when the even split is above it. A split above 40 g per meal, a target above 40 g and gaps under 2 hours each get a warning, and meals per day must be a whole number from 2 to 8.

The ISSN's 2017 position stand suggests 0.25 g of high-quality protein per kg of body weight, or 20 to 40 g, per dose, spread evenly every 3 to 4 hours.

Fun Fact: The same ISSN position stand notes that 30 to 40 g of casein before sleep raises overnight muscle protein synthesis and metabolic rate.

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