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Pressure calculator

GCSEA-level Forces

Pressure is the force acting normally on a surface divided by the area of the surface.

p = F / A

This free calculator is for GCSE and A-level physics. Choose the quantity you want to find, enter the other values with their units, and it shows the working in the layout used in exams, with the answer to the number of significant figures you choose. The values shown are an example. Change them to your own.

Quantity to find

24000 Pa

Working

  1. Write the equation
    p = F / A
  2. Substitute the values
    p = 600 ÷ 0.025
  3. Calculate
    p = 24000 Pa
  4. Give the answer to 3 significant figures
    p = 24000 Pa
    In standard form: 2.40 × 104 Pa

Worked example

Find p, the pressure. Given: force F = 600 N; area A = 0.0250 m².

  1. Write the equation
    p = F / A
  2. Substitute the values
    p = 600 ÷ 0.025
  3. Calculate
    p = 24000 Pa
  4. Give the answer to 3 significant figures
    p = 24000 Pa
    In standard form: 2.40 × 104 Pa

Symbols and units

SymbolQuantitySI unit
pPressurePa
FForceN
AAream²

Pressure: rearranged

  • To find pressure: p = F / A
  • To find force: F = p A
  • To find area: A = F / p

Exam tip

Convert cm² to m² by dividing by 10 000, not 100. One pascal is one newton per square metre.

Common questions

What is the formula for pressure?

The equation is p = F / A, where p is the pressure (Pa); F is the force (N); A is the area (m²).

What units should I use for pressure?

In SI units: pressure in Pa, force in N, area in m². The calculator also accepts common alternatives such as kilometres, grams or minutes, and converts them for you.

How do I rearrange p = F / A?

Rearranging gives these forms: to find pressure: p = F / A. to find force: F = p A. to find area: A = F / p.

Practise pressure questions

Press the button for a question with random numbers. Work it out on paper first, then type your answer.

Related

Read the full explanation on the Pressure from force and area formula page. More forces equations: Newton’s second law, Weight, Moment of a force, Hooke’s law, Pressure in a liquid, Density, Horizontal component of a force, Vertical component of a force. See the full list on the physics equation calculator page.