THE NUMBERS, EXPLAINED
How to use this calculator.
Books are listened to sequentially and can continue between sessions. A fixed speed is used per book; breaks are outside the session budget.
Start with your inputs
Enter audiobook source lengths (minutes), playback speed by book (multipliers), listening session duration (minutes). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Audiobook source lengths (minutes) | 120,180 |
| Playback speed by book (multipliers) | 1.5,2 |
| Listening session duration (minutes) | 30 |
A worked example
With the example inputs above, adjusted listening times (minutes) is 80, 90. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Adjusted listening times (minutes) | 80, 90 |
| Total listening time (minutes) | 170 |
| Session each book finishes (count from 1) | 3, 6 |
How this is calculated
Adjusted listening times (minutes)
Divide each source duration by its playback speed.
Total listening time (minutes)
Add adjusted book times.
Session each book finishes (count from 1)
Divide cumulative adjusted time by session duration and round up.
Symbols and units
- a
- Audiobook source lengths (minutes)
- b
- Playback speed by book (multipliers)
- c
- Listening session duration (minutes)
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions and limits
Books are listened to sequentially and can continue between sessions. A fixed speed is used per book; breaks are outside the session budget.
Calculations use the values you enter. Blank or invalid inputs show an error instead of silently substituting zero. Results are displayed to useful precision; calculations retain the underlying numeric precision.
Questions about this tool
What does the result tell me?
Adjusted listening times (minutes); Total listening time (minutes); Session each book finishes (count from 1). The result applies to the method and inputs described above. Check the units and assumptions before using it in a decision.
Why might another calculator differ?
Differences in units, rounding, timing or model definitions can produce different answers. Compare the input definitions and the method, rather than only the final number. For this tool: Books are listened to sequentially and can continue between sessions. A fixed speed is used per book; breaks are outside the session budget.
Are my inputs stored or sent to AI?
Calculations on this page happen in your browser. The separate AI question finder sends its submitted conversation to OpenAI; these calculator fields are not sent. Favourites and recent tool names are stored locally. A shared link contains the inputs you choose to include.
Further reading
OpenStax Prealgebra 2e — arithmetic and proportions ↗
Background reading; this does not imply endorsement or independent review of SumFizz.
Review status
Software example and browser checks are recorded in our quality report. No external expert review is claimed. Created with coding assistance; calculations run as ordinary browser code.
Read the quality report →