The transmon, a fabrication-friendly superconducting qubit, remains a leading candidate for scalable quantum computing. Recent advances in tunable couplers have accelerated progress toward high-performance quantum processors. However, extending coherent interactions beyond millimeter scales to enhance quantum connectivity presents a critical challenge. Here we introduce a hybrid-mode coupler exploiting resonator-transmon hybridization to simultaneously engineer the two lowest-frequency modes, enabling high-contrast coupling between transmons spaced at a centimeter-scale distance. For a 1-cm coupler, we experimentally demonstrate flux-tunable hybrid modes and measure strong $XX$ and $ZZ$ couplings between qubits exceeding 23 and 10 MHz, respectively, under current conditions, in agreement with an effective two-channel model. Our theoretical model further suggests $ZZ$ coupling strengths reaching 100 MHz, with modulation contrasts exceeding ${10}^4$. This work provides an efficient pathway to mitigate the inherent connectivity constraints imposed by short-range interactions, enabling transmon-based architectures compatible with hardware-efficient quantum tasks.

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• Optoelectronics
• Quantum circuits
• Quantum control
• Quantum information with solid state qubits
• Quantum interconnects
• Superconducting devices
• Cavity resonators
• Microwave techniques