⚖️ Weight & Balance Calculator
Enter each loading station's weight and arm — empty aircraft, crew, passengers, baggage, fuel — to find your total weight, total moment, and centre of gravity before you fly.
🛩️ Are You In the Envelope?
What is a Weight & Balance Calculator?
It adds up the weight and the moment of every station in the aircraft — empty weight, people, bags, and fuel — and works out where the loaded centre of gravity falls. You get the total weight to compare against gross limits and the CG arm to compare against the forward and aft limits of the envelope.
Use it to check your arithmetic. Add a row for each station, enter its weight and arm, and read off the CG. It never tells you a load is within limits: the aircraft's own weight and balance record and the envelope in its POH/AFM are the authority, and a figure near a limit must be checked unrounded against them.
❓ Frequently Asked Questions
How is centre of gravity calculated?
For each loading station you multiply its weight by its arm — the distance from the datum — to get a moment. The calculator sums all the weights and all the moments, then divides total moment by total weight to find the centre of gravity, expressed as an arm in the same units you entered (inches or metres from the datum). Add a row for every station: empty aircraft, crew, passengers, baggage, and fuel.
What are the datum, arm, and moment?
The datum is a fixed reference line the manufacturer chooses, often at the firewall or nose. An arm is how far a station sits from that datum; a moment is weight times arm, a measure of the turning effect about the datum. Working in moments lets you combine loads at different positions into a single centre of gravity. Your aircraft's weight-and-balance data sheet lists the arm for each station.
Why does weight and balance matter?
Being over gross weight lengthens the takeoff roll, cuts climb, and stresses the airframe, while a centre of gravity outside limits makes the aircraft unstable or even uncontrollable — a forward CG can make it hard to flare, an aft CG can make a stall unrecoverable. Every flight must fall within both the weight and CG envelope published for the aircraft, so this check is a legal and safety essential.
Does this account for fuel burn shifting the CG?
This calculates the CG for the loading you enter — typically your takeoff configuration. Because fuel sits at its own arm, burning it off during the flight moves the CG, so a load that's in limits at takeoff can drift out by landing. For a full check, run the numbers for both takeoff and zero-fuel or landing weight. It's an arithmetic aid only; the aircraft's weight and balance record and POH/AFM envelope are the authority.