PWM duty cycle calculator

Period must be strictly positive: a zero period would divide by zero, so the API returns a clear invalid_input error instead of inventing Infinity or NaN.

What duty cycle and average voltage mean for a PWM waveform

The check path recomputes ton over T and D times V with the same fixed rounding used for published fields, so a successful response always ships with steps you can assert in tests or worksheets without floating-point ambiguity between the Worker and the browser.

How to call the API and what comes back

On-time must be non-negative; a negative high interval is rejected for this ideal digital PWM model. Prefer sending numbers rather than pre-formatted strings when you control the client; string numbers are accepted only when they match a strict finite numeric pattern including optional scientific notation. Send a JSON body with three required finite numbers: on_time (aliases ton, t_on, high_time, pulse_width, and pw) for the high interval, period (aliases T, t_period, cycle_time, and pwm_period) for the full cycle length in the same time unit, and voltage (aliases V, vcc, v_supply, amplitude, and supply_voltage) for the high-level amplitude in volts. Absolute values must stay within the published limit of one trillion so intermediate ratios and products remain finite in IEEE double precision on the Worker and in the browser. Period must be strictly positive; values whose absolute magnitude is at or below one times ten to the minus fifteen are treated as zero and rejected, and any strictly negative period is also invalid_input. On success the response echoes rounded on_time and ton, period and T, voltage and V, sets duty, duty_cycle, and duty_fraction to the same dimensionless fraction, duty_percent to one hundred times D, average_voltage and Vavg to D times V in volts, off_time to period minus on_time, frequency to one over period, formula to the documented D and Vavg strings, equation to a human-readable substitution line, unit labels for fraction, percent, and volts, message to a short English summary, and steps to an ordered array of given values, formulas, duty, percent, off time, frequency, average voltage, and summary. Failed validation—missing fields, non-numeric strings, non-finite numbers, values outside absolute limits, zero or negative period, negative on-time, or a non-finite ratio—returns invalid_input and is never charged. Pricing is a flat $0.002 per successful request with unit item and zero marginal unit price.

Practical tips, limits, and related searches

Keep on-time, period, and voltage inside the published absolute range so the ratio and product stay finite under the magnitude cap. Use the same time unit for ton and T before you call if you want duty already dimensionless and frequency already in the reciprocal of that unit without mental rescaling afterward. Prefer this capability when you already have scalar on-time, period, and supply voltage and only need D, duty percent, and ideal Vavg; if your source is a microcontroller compare match and clock divider, convert those into seconds or ticks first so both intervals share a unit. When teaching, pair examples: ton equals two, T equals ten, V equals five yields twenty percent and one volt average; ton equals five, T equals ten, V equals twelve yields fifty percent and six volts; ton equals zero with positive T yields zero duty and zero average; and setting period to zero demonstrates the hard invalid_input path. Failed tasks that return invalid_input do not consume prepaid balance, which keeps exploratory scripts cheap when learners deliberately set period to zero. Round-trip checks are easy: recompute ton divided by T and multiply by V by hand and confirm the published duty and average_voltage match within the same twelve-decimal rounding, and confirm that scaling ton and T by the same positive factor leaves D and Vavg unchanged as the formula predicts.