CAN & CAN FD bus-load estimator
Estimate the wire time and combined bus utilisation of periodic messages, including frame overhead and conservative stuffing allowances.
Your result
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Plan utilisation with stated assumptions.
The lower estimate excludes dynamic stuffing. The upper planning estimate adds conservative stuffing; CAN FD always includes its fixed CRC stuff bits. All frames include three intermission bits. With bitrate switching, BRS and CRC-delimiter transitions are treated as whole-bit phase boundaries; each phase receives a conservative stuffing allowance. This is a planning estimate, with no errors, retries, arbitration-delay prediction, or extra event traffic.
bus load (%) = Σ(frame duration / message period) × 100
Classical CAN: 47 + 8×bytes (standard), 67 + 8×bytes (extended), before stuffing