THE NUMBERS, EXPLAINED
How to use this calculator.
Word counts are supplied using a consistent counting convention. Threshold is your editorial choice; reading speed alone cannot establish caption accessibility.
Start with your inputs
Enter caption word counts, caption display durations (seconds), user-chosen review threshold (words/minute). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Caption word counts | 6,10,8 |
| Caption display durations (seconds) | 3,4,4 |
| User-chosen review threshold (words/minute) | 140 |
A worked example
With the example inputs above, reading rates by caption (words/minute) is 120, 150, 120. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Reading rates by caption (words/minute) | 120, 150, 120 |
| Caption rows over chosen threshold | 2 |
| Duration-weighted overall reading rate (words/minute) | 130.909091 |
How this is calculated
Reading rates by caption (words/minute)
Divide each word count by display seconds and multiply by 60.
Caption rows over chosen threshold
Select captions exceeding the supplied rate.
Duration-weighted overall reading rate (words/minute)
Divide total words by total display time.
Symbols and units
- a
- Caption word counts
- b
- Caption display durations (seconds)
- c
- User-chosen review threshold (words/minute)
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
Word counts are supplied using a consistent counting convention. Threshold is your editorial choice; reading speed alone cannot establish caption accessibility.
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?
Reading rates by caption (words/minute); Caption rows over chosen threshold; Duration-weighted overall reading rate (words/minute). 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: Word counts are supplied using a consistent counting convention. Threshold is your editorial choice; reading speed alone cannot establish caption accessibility.
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
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 →