Tempo in a piece of music is often stated with conventional Italian terms (recall that the Renaissance began in Italy). Since the invention of the metronome, tempo is also given in beats per minute (bpm). However, a slow tempo is one in which a beat takes more time, and a fast tempo is one in which a beat takes less time. So it would make sense to measure tempo by amount of time per beat.
Since bpm in music ranges from about 20 to 200, it would be appropriate to convert it to units of jiffies per beat, with a jiffy defined as one-sixtieth of a second (so 60 jiffies make one second). To convert from X bpm to Y jpb, divide X into 3600; that is, Y jpb = 3600 / X.
Here are suggested jpb tempo values from slowest to fastest based on the list here:
- Larghissimo – very, very slow (24 bpm and under) = 150 jpb and over
- Grave – very slow (25–45 bpm) = 80 to 144 jpb
- Largo – broadly (40–60 bpm) = 60 to 90 jpb
- Lento – slowly (45–60 bpm) = 60 to 80 jpb
- Larghetto – rather broadly (60–66 bpm) = 54 to 60 jpb
- Adagio – slowly with great expression (66–76 bpm) = 47 to 54 jpb
- Adagietto – slower than andante (72–76 bpm) = 47 to 50 jpb
- Andante – at a walking pace (76–108 bpm) = 50 to 33 jpb
- Andantino – slightly faster than andante (80–108 bpm) = 33 to 45 jpb
- Marcia moderato – moderately, in the manner of a march (83–85 bpm) = 42 to 43 jpb
- Andante moderato – between andante and moderato (92–112 bpm) = 32 to 39 jpb
- Moderato – at a moderate speed (108–120 bpm) = 30 to 33 jpb
- Allegretto – by the mid 19th century, moderately fast (112–120 bpm) = 30 to 32 jpb
- Allegro moderato – close to, but not quite allegro (116–120 bpm) = 30 to 31 jpb
- Allegro – fast, quickly, and bright (120–156 bpm) = 23 to 30 jpb
- Vivace – lively and fast (156–176 bpm) = 20 to 23 jpb
- Vivacissimo – very fast and lively (172–176 bpm) = 20 to 21 jpb
- Allegrissimo or Allegro vivace – very fast (172–176 bpm) = 20 to 21 jpb
- Presto – very, very fast (168–200 bpm) = 18 to 21 jpb
- Prestissimo – even faster than presto (200 bpm and over) = 18 jpb and under
Music tempo measured by jpb is similar to lenticity in physics previously discussed (e.g., here).
Note:
The above measure of tempo is equivalent to seconds per 60 beats.