Static pressure and stagnation pressure are related by:

  
    
      
        
          p
          
            0
          
        
        =
        
          
            1
            2
          
        
        ρ
        
          v
          
            2
          
        
        +
        p
      
    
    {\displaystyle p_{0}={\frac {1}{2}}\rho v^{2}+p}
  where 

  
    
      
        
          p
          
            0
          
        
      
    
    {\displaystyle p_{0}}
   is the stagnation pressure,

  
    
      
        ρ
      
    
    {\displaystyle \rho }
   is the density,

  
    
      
        v
      
    
    {\displaystyle v}
   is the flow velocity,

  
    
      
        p
      
    
    {\displaystyle p}
   is the static pressure.The pressure of a moving fluid can be measured using a Pitot tube, or one of its variations such as a Kiel probe or Cobra probe, connected to a manometer.
For example, a wide but shallow lake with a depth of 3 m (10 ft) exerts only half the average pressure that a small 6 m (20 ft) deep pond does. (The total force applied to the longer dam will be greater, due to the greater total surface area for the pressure to act upon. But for a given 5-foot (1.5 m)-wide section of each dam, the 10 ft (3.0 m) deep water will apply one quarter the force of 20 ft (6.1 m) deep water). A person will feel the same pressure whether their head is dunked a metre beneath the surface of the water in a small pool or to the same depth in the middle of a large lake. If four vases contain different amounts of water but are all filled to equal depths, then a fish with its head dunked a few centimetres under the surface will be acted on by water pressure that is the same in any of the vases. If the fish swims a few centimetres deeper, the pressure on the fish will increase with depth and be the same no matter which vase the fish is in. If the fish swims to the bottom, the pressure will be greater, but it makes no difference what vase it is in. All vases are filled to equal depths, so the water pressure is the same at the bottom of each vase, regardless of its shape or volume.