The only way to find the volumetric size of Nespresso cups, is by taking a picture in my office.

opened container with circular nespresso capsules
  • 25 ml / 0.85 fl o
  • 40 ml / 1.35 fl o
  • 110 ml / 3.75 fl o

The size of Nespresso coffee cups pictured above. Here you go internet, you are welcome.