THE NUMBERS, EXPLAINED
How to use this calculator.
Area basis must consistently count one or both pane faces. This is measured productivity, not an access-method recommendation.
Start with your inputs
Enter pane areas completed by access class (m²), actual task times by class (hours), nonproductive access/setup times by class (hours). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Pane areas completed by access class (m²) | 100,60 |
| Actual task times by class (hours) | 2,3 |
| Nonproductive access/setup times by class (hours) | 0.5,1 |
A worked example
With the example inputs above, productive rates by class (m²/hour) is 50, 20. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Productive rates by class (m²/hour) | 50, 20 |
| Elapsed rates by class (m²/hour) | 40, 15 |
| Blended elapsed productivity (m²/hour) | 24.615385 |
How this is calculated
Productive rates by class (m²/hour)
Divide completed pane area by actual cleaning time.
Elapsed rates by class (m²/hour)
Include setup and access time in the denominator.
Blended elapsed productivity (m²/hour)
Divide combined area by all elapsed hours.
Symbols and units
- a
- Pane areas completed by access class (m²)
- b
- Actual task times by class (hours)
- c
- Nonproductive access/setup times by class (hours)
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
Area basis must consistently count one or both pane faces. This is measured productivity, not an access-method recommendation.
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?
Productive rates by class (m²/hour); Elapsed rates by class (m²/hour); Blended elapsed productivity (m²/hour). 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: Area basis must consistently count one or both pane faces. This is measured productivity, not an access-method recommendation.
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: Describe and Identify Cost Drivers ↗
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 →