The Coulter counter detects and sizes particles volumetrically by the modulation of electrical current through a small fluidic aperture. Since its invention in the 1950s, resistive pulse sensing by the label-free Coulter principle has quickly become a standard for measuring colloidal particles and biological cells. However, the solid-state apertures employed in conventional Coulter counting are prone to clogging by impurities, which limits the smallest off-the-shelf apertures to 20 microns in diameter. Consequently, the smallest detectable particle diameter is restricted to 1 micron or so. To circumvent the clogging problem of solid apertures, we have come up with a liquid sensing aperture for Coulter counting. In our device, an electrohydrodynamic liquid bridge with a diameter of approximately 10 microns is formed, and the electrical current oscillogram is used to detect particles. Because the sensing aperture is defined by the air/liquid interface, the deformable aperture is immune to clogging; it “swallows” large agglomerates as a snake does. Although the proof-of-principle has been demonstrated using micron-sized particles, resistive sensing of submicron particles is foreseeable because electrohydrodynamic techniques are known to produce tiny cone-jets with a diameter down to 10 nanometers. The development of nonclogging electrohydrodynamic Coulter counters has major practical implications, particularly given the potential to extend the analysis range down to nanometric sizes. The technique can bridge the gap between the analysis ranges of conventional Coulter counters and solid-state nanopores, while overcoming the frustrating and costly clogging issue that plagues them.