Aisha K.
Mar 12, 2026
Clean layout and the results update instantly. Exactly what I needed for a quick planning check.
Health, Fitness & Wellness
Weight Gain Calorie Surplus Calculator for Muscle
Surplus kcal/day = (weekly lb gain × 3,500) ÷ 7 added to TDEE.
Calculate a daily surplus and timeline to gain weight at a chosen rate. Estimates only—not a diagnosis or prescription.
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Inputs
15005000
0.252
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Recommendations
Tailored to your live inputs and result—guidance only, not professional advice.
- Interpret
Treat this as a planning estimate
Primary result: Daily surplus target = 3,050 kcal. Re-run with optimistic and pessimistic inputs to understand the range—not just a single point.
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Plain-English guide
Terms & how it works
Confused by a field? Read the short definitions here while you use the tool.
TDEE (kcal/day)
The “TDEE (kcal/day)” value used in this tool’s formula. Adjust it to see results update live.
Gain goal (lb/week)
The “Gain goal (lb/week)” value used in this tool’s formula. Adjust it to see results update live.
How this calculator works
Calculate a daily surplus and timeline to gain weight at a chosen rate. Estimates only—not a diagnosis or prescription. Surplus kcal/day = (weekly lb gain × 3,500) ÷ 7 added to TDEE. Example: TDEE 2,800 + 500 kcal surplus → ~1 lb/week gain target.
Surplus kcal/day = (weekly lb gain × 3,500) ÷ 7 added to TDEE.
Example: TDEE 2,800 + 500 kcal surplus → ~1 lb/week gain target.
When to use this Weight Gain
Common use cases
- Calculate a daily surplus and timeline to gain weight at a chosen rate.
- Sanity-check with this case: TDEE 2,800 + 500 kcal surplus → ~1 lb/week gain target.
- The relationship is: Surplus kcal/day = (weekly lb gain × 3,500) ÷ 7 added to TDEE.
Localized examples
- Health, Fitness & Wellness: the example on this page uses the same formula as the widget.
What you get
- Fields: TDEE (kcal/day), Gain goal (lb/week)
- Surplus kcal/day = (weekly lb gain × 3,500) ÷ 7 added to TDEE.
- Example on the page: TDEE 2,800 + 500 kcal surplus → ~1 lb/week gain target.
How to Calculate Weight Gain Step-by-Step
- 1Enter TDEE (kcal/day), Gain goal (lb/week). Use the values you have, not a catalog average, unless that is all you know.
- 2Surplus kcal/day = (weekly lb gain × 3,500) ÷ 7 added to TDEE.
- 3Worked case: TDEE 2,800 + 500 kcal surplus → ~1 lb/week gain target.
- 4If this number would change a drug, a diet, or a return-to-play call, take it to a clinician. The page never examined you.
Governing formula
Surplus kcal/day = (weekly lb gain × 3,500) ÷ 7 added to TDEE.
TDEE 2,800 + 500 kcal surplus → ~1 lb/week gain target.
Example: set TDEE (kcal/day) = 2,800, Gain goal (lb/week) = 0.5, then read the result.
Variable definitions
- tdee
TDEE (kcal/day)
The “TDEE (kcal/day)” field. Default 2800; typical range 1500–5000.
- weeklyGainLbs
Gain goal (lb/week)
The “Gain goal (lb/week)” field. Default 0.5; typical range 0.25–2.
- The formula (Surplus kcal/day = (weekly lb gain × 3,500) ÷ 7 added to TDEE.) does not see labs, medications, sleep, or injury history. A clinician does.
- Nothing here is uploaded for the calculation itself.
Frequently Asked Questions
Surplus kcal/day = (weekly lb gain × 3,500) ÷ 7 added to TDEE.
Related calculators
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- Body Recomposition PlannerBody recomposition planner with a training-volume deficit cap — more hard sets means a smaller deficit and higher protein.
- TDEE CalculatorFind total daily energy expenditure from BMR and activity level.
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- Bulk & Cut Macro PlannerBulk and cut macro calculator for lifters: set lean bulk or cutting calories from TDEE, weekly rate, and training experience—with protein-forward macros and training-day carb cycling.
- Reverse Diet PlannerReverse diet planner with adaptive weekly calorie bumps — smaller increases when the scale is still dropping too fast.
- Body Recomposition PlannerBody recomposition planner with a training-volume deficit cap — more hard sets means a smaller deficit and higher protein.
- TDEE CalculatorFind total daily energy expenditure from BMR and activity level.
- Calorie Deficit CalculatorTurn a weekly fat-loss goal into a daily calorie deficit and target.
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Reviews & Ratings
See what others think about this tool, then leave your own rating to help improve CalculioHub.
4.8
out of 5.0
4 reviews
Daniel R.
Feb 28, 2026
Very usable on mobile. Would love a save/export option later, but the math feels solid.
Priya S.
Feb 3, 2026
The FAQ section answered my questions before I even had to search. Smooth dark mode too.
Marcus L.
Jan 19, 2026
Simple inputs, clear outputs. This replaced three bookmarks I used to juggle.
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