This paper presents a single-shot interferometric measurement of fermion parity in InAs-Al hybrid devices, a key operation in topological quantum computation. The experiment uses a nanowire coupled to quantum dots to measure the quantum capacitance, which is sensitive to the magnetic flux and the combined fermion parity of the dot-Majorana zero mode (MZM) system. The measurement reveals a bimodal quantum capacitance signal with a period of h/2e, indicating a flux-dependent parity switch. The results show a long dwell time (over 1 ms) in the two parity states, consistent with a low poisoning rate of non-equilibrium quasiparticles. The measurement has a 1% error probability, demonstrating the feasibility of parity measurement in topological qubits. The device design includes a 1D topological superconductor with MZMs at the ends, and quantum dots that form an interferometer. The measurement technique uses dispersive gate sensing to read out the quantum capacitance, enabling single-shot parity determination. The results are consistent with a topological phase where MZMs are separated by 3 µm and have a low poisoning rate. The study also discusses the implications of the results for topological quantum computation, including the robustness against errors and the potential for scalable quantum computing. The paper highlights the importance of interferometric measurements in verifying the topological phase and the role of quantum capacitance in detecting fermion parity. The findings support the use of measurement-only topological quantum computation, where parity measurements are sufficient to perform all topologically protected operations. The study also addresses the challenges of device design, including the need for a large lever arm and the suppression of non-equilibrium quasiparticles. The results demonstrate the potential of InAs-Al hybrid devices for topological quantum computation and provide insights into the behavior of low-energy states in topological superconductors. The paper concludes with a discussion of the broader implications for quantum computing, including the potential for error correction and the development of scalable quantum devices.This paper presents a single-shot interferometric measurement of fermion parity in InAs-Al hybrid devices, a key operation in topological quantum computation. The experiment uses a nanowire coupled to quantum dots to measure the quantum capacitance, which is sensitive to the magnetic flux and the combined fermion parity of the dot-Majorana zero mode (MZM) system. The measurement reveals a bimodal quantum capacitance signal with a period of h/2e, indicating a flux-dependent parity switch. The results show a long dwell time (over 1 ms) in the two parity states, consistent with a low poisoning rate of non-equilibrium quasiparticles. The measurement has a 1% error probability, demonstrating the feasibility of parity measurement in topological qubits. The device design includes a 1D topological superconductor with MZMs at the ends, and quantum dots that form an interferometer. The measurement technique uses dispersive gate sensing to read out the quantum capacitance, enabling single-shot parity determination. The results are consistent with a topological phase where MZMs are separated by 3 µm and have a low poisoning rate. The study also discusses the implications of the results for topological quantum computation, including the robustness against errors and the potential for scalable quantum computing. The paper highlights the importance of interferometric measurements in verifying the topological phase and the role of quantum capacitance in detecting fermion parity. The findings support the use of measurement-only topological quantum computation, where parity measurements are sufficient to perform all topologically protected operations. The study also addresses the challenges of device design, including the need for a large lever arm and the suppression of non-equilibrium quasiparticles. The results demonstrate the potential of InAs-Al hybrid devices for topological quantum computation and provide insights into the behavior of low-energy states in topological superconductors. The paper concludes with a discussion of the broader implications for quantum computing, including the potential for error correction and the development of scalable quantum devices.