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Spacecraft Mass Budget Calculator

Estimate spacecraft dry mass, propellant mass, and payload fraction from subsystem mass percentages.

Inputs

lb
%
%
%
%
%
%

Results

Dry Mass

1,250 kg

≈ 16 adults

Total Launch Mass

2,466.88 kg

≈ 5 grand pianos

Propellant Mass1,216.88 kg
Payload Fraction20.27%
Structural Fraction20%
How to Use This Calculator
  1. Enter payload mass (kg) — the science instruments or communication payload being carried.
  2. Set subsystem mass percentages for structure, power, propulsion, thermal, and communications.
  3. Review dry mass, required propellant mass based on mission delta-V, and total launch mass.
  4. Check payload fraction and structural fraction against your launch vehicle's performance envelope.
  5. Iterate subsystem percentages to reduce total mass if launch vehicle capacity is exceeded.

How the result changes with Payload Mass

Payload MassDry MassTotal Launch Mass
10,00125,002.5 kg49,342.54 kg
35,00187,502.5 kg172,686.56 kg
65,000162,500 kg320,694.45 kg
90,000225,000 kg444,038.47 kg

What each input means

Payload Mass
Mass of the mission payload that the spacecraft must carry.
Structure Mass
Percentage of dry mass allocated to structural components (chassis, panels, etc.).
Power System
Percentage of dry mass allocated to power generation and storage (solar arrays, batteries).
Propulsion System
Percentage of dry mass for the propulsion hardware (engines, tanks, plumbing).
Thermal Control
Percentage of dry mass for thermal control systems (radiators, heaters, insulation).
Communications
Percentage of dry mass for communication hardware (antennas, transponders).
Mass Margin
Design margin to account for mass growth during development. Typically 10–25%.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Payload Mass = 500, Structure Mass = 20, Power System = 15, Propulsion System = 5 = 7 input(s) provided
  2. Calculate Dry Mass
    Dry Mass
    1250 = 1250
  3. Calculate Total Launch Mass
    Total Launch Mass
    2466.88 = 2466.88
  4. Calculate Propellant Mass
    Propellant Mass
    1216.88 = 1216.88
  5. Calculate Payload Fraction
    Payload Fraction
    20.27 = 20.27

Engine last updated . Checked against 2 independently-derived tests — how we verify calculators.

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