Free · Physics models
NASA Gravity-Ratio Scale Equivalents
Compare Earth-calibrated scale-equivalent readings using published planetary gravity ratios.
- Formula & worked example
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Calculator inputs
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How to use this calculator
- Enter the known values in the units shown. Results update as you type.
- Where results are editable, change one to solve backwards. Lock a value to hold it fixed.
- Use the worked example to check the method. Reset restores the starting fields.
Private by default
Inputs and results stay in this browser tab. Bookify does not upload or store the values you enter.
Formula and method
Mercury = 3.7800; Venus = 9.0700. This worked example uses the displayed units and declared assumptions.
Mercury = Earth reading × .378; Venus = Earth reading × .907; Mars = Earth reading × .377; Jupiter = Earth reading × 2.36; Saturn = Earth reading × .916; Uranus = Earth reading × .889; Neptun = Earth reading × 1.12; Pluto = Earth reading × .071; Moon = Earth reading × .166; Ganymede = Earth reading × .146
Worked example
Enter these known values and leave the other values blank.
- Your weight on Earth 🌎
- 10 kg
- Mercury
- 3.8 kg
- Venus
- 9.1 kg
- Mars
- 3.8 kg
- Jupiter
- 23.6 kg
- Saturn
- 9.2 kg
- Neptune
- 11.2 kg
- Uranus
- 8.9 kg
- Pluto
- 0.7 kg
- The Moon
- 1.66 kg
- Ganymede
- 1.46 kg
Assumptions and limitations
- These outputs are Earth-scale-equivalent readings, not changes in mass. The model uses published rounded NASA gravity ratios rather than a location-specific gravity field. Gas giants have no solid surface; atmospheric reference levels and rotation affect effective gravity.
- The ratio fact sheet was last updated 18 March 2025. Ganymede uses the rounded 0.146 reference from 1.428 m/s². Inputs and inverse outputs are positive scale readings.
Common questions
What assumptions apply?
These outputs are Earth-scale-equivalent readings, not changes in mass. The model uses published rounded NASA gravity ratios rather than a location-specific gravity field. Gas giants have no solid surface; atmospheric reference levels and rotation affect effective gravity.
Which unknowns can I solve?
Editable controls preserve the supported captured inverse branches. Clear the desired unknown and provide enough independent known quantities; singular or underdetermined inverses may remain incomplete.
References
- NASA Planetary Fact Sheet, Earth ratios
- NASA Galilean satellite fact sheet
- Calculation definition and unit reference
Use the NASA Earth-ratio fact sheet gravity values (last updated 18 March 2025), with Ganymede rounded ratio 0.146 from its 1.428 m/s² reference. Results are kg-equivalent readings of an Earth-calibrated scale, not changed mass or force in newtons. Gas giants refer to the stated atmospheric reference level and real effective gravity varies with location.