Calculation Methodology
Beatglass calculates production timing from standard tempo and digital-audio relationships. Intermediate calculations are not presentation-rounded; formatting happens only at the result boundary.
Tempo and note duration
Quarter-note seconds = 60 / BPM. Tempo frequency in Hz = BPM / 60. Whole-note duration = quarter-note duration × 4. Note duration = whole-note duration × note fraction × modifier.
Straight values use a modifier of 1. Dotted modifier = 1.5. Triplet modifier = 2/3.
Meter behavior
Beat-unit duration = whole-note duration / meter denominator. Bar duration = beat-unit duration × meter numerator. The meter denominator therefore determines the beat unit; a bar is not always a fixed number of quarter notes.
Samples and time
Seconds = samples / sample rate. Samples = seconds × sample rate. Exact fractional mathematical sample counts are distinct from nearest discrete sample frames: for 1 ms at 44.1 kHz, the exact count is 44.1 samples and the nearest frame is 44.
Precision
Displayed milliseconds use up to 4 decimal places, seconds and Hz use up to 6, and BPM uses up to 3. Unusual but valid positive BPM and sample-rate values are accepted.
Worked vectors
At 120 BPM, a quarter note is 500 ms, an eighth is 250 ms, a dotted eighth is 375 ms, an eighth-note triplet is 166.666666… ms, and tempo frequency is 2 Hz. At 48 kHz, a 120 BPM quarter note is 24,000 samples and a 4/4 bar is 2 seconds or 96,000 samples. 2,048 samples at 48 kHz is 42.666666… ms; 10 ms at 96 kHz is 960 samples; and 16 beats in 10 seconds is 96 BPM.
Limitations
These tools calculate mathematical timing relationships. They do not measure hardware or device latency, and they do not analyze uploaded audio.