Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
Gross weight (lb)
2,290
CG arm (in)
43.24
Gross weight check
Under gross by 160 lb
Total moment (lb-in)
99,030
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter empty weight (lb).
- 2Enter empty cg arm (in).
- 3Enter front seats (lb).
- 4Enter front seat arm (in).
- 5Enter rear seats (lb).
- 6Enter rear seat arm (in).
- 7Enter fuel (gal).
- 8Enter fuel arm (in).
- 9Enter baggage (lb).
- 10Enter baggage arm (in).
- 11Enter max gross weight (lb).
- 12Read your gross weight (lb) on the right — it updates as you type.
- 13Hit Share to keep the scenario or send it to someone.
About this calculator
Sum station weights and moments to get gross weight and CG arm. Educational estimate — always fly the numbers in your POH.
Worked example
Using the values the calculator loads with:
Inputs
- Empty weight: 1500 lb
- Empty CG arm: 39 in
- Front seats: 340 lb
- Front seat arm: 37 in
- Rear seats: 160 lb
- Rear seat arm: 73 in
- Fuel: 40 gal
- Fuel arm: 48 in
- Baggage: 50 lb
- Baggage arm: 95 in
- Max gross weight: 2450 lb
Results
- Gross weight (lb): 2,290
- CG arm (in): 43.24
- Gross weight check: Under gross by 160 lb
- Total moment (lb-in): 99,030
What each field means
Inputs
- Empty weight (lb)
- The empty weight used in the calculation, measured in lb. Starts at 1500 lb so you have a working example on load.
- Empty CG arm (in)
- The empty cg arm used in the calculation, measured in in. Starts at 39 in so you have a working example on load.
- Front seats (lb)
- The front seats used in the calculation, measured in lb. Starts at 340 lb so you have a working example on load.
- Front seat arm (in)
- The front seat arm used in the calculation, measured in in. Starts at 37 in so you have a working example on load.
- Rear seats (lb)
- The rear seats used in the calculation, measured in lb. Starts at 160 lb so you have a working example on load.
- Rear seat arm (in)
- The rear seat arm used in the calculation, measured in in. Starts at 73 in so you have a working example on load.
- Fuel (gal)
- The fuel used in the calculation, measured in gal. Starts at 40 gal so you have a working example on load.
- Fuel arm (in)
- The fuel arm used in the calculation, measured in in. Starts at 48 in so you have a working example on load.
- Baggage (lb)
- The baggage used in the calculation, measured in lb. Starts at 50 lb so you have a working example on load.
- Baggage arm (in)
- The baggage arm used in the calculation, measured in in. Starts at 95 in so you have a working example on load.
- Max gross weight (lb)
- The max gross weight used in the calculation, measured in lb. Starts at 2450 lb so you have a working example on load.
Results
- Gross weight (lb)
- Returned as a whole number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- CG arm (in)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Gross weight check
- Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total moment (lb-in)
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the aircraft weight & balance calculator work?
Sum station weights and moments to get gross weight and CG arm. Educational estimate — always fly the numbers in your POH. The underlying maths is: CG = Σ(weight × arm) ÷ Σ(weight).
What do I need to enter?
11 values: empty weight, empty cg arm, front seats, front seat arm, rear seats, rear seat arm, fuel, fuel arm, baggage, baggage arm, and max gross weight. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the gross weight (lb) result mean?
It is returned as a whole number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Estimates assume standard, average conditions — local rules, pricing, and materials vary.
Who is this tool for?
It's built for anyone doing everyday planning maths — a quick estimate that would otherwise need four browser tabs and a calculator app.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Aircraft Weight & Balance Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/aircraft-weight-balance
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/aircraft-weight-balance" target="_blank" rel="noopener">Aircraft Weight & Balance Calculator — RevenueLab</a> (2026).</p>
Source: [Aircraft Weight & Balance Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/aircraft-weight-balance) (2026).