THE NUMBERS, EXPLAINED
How to use this calculator.
Seals both the top and bottom. Centre seal uses one lengthwise strip per face. H seal adds two crosswise strips per face. Each strip gets the entered extension at both ends. Does not include waste, rework or tape stretch.
Start with your inputs
Enter carton length (cm), carton width (cm), tape extension at each end of a strip (cm), centre seal (1) or h seal (2), cartons, tape roll length (m). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Carton length (cm) | 40 |
| Carton width (cm) | 30 |
| Tape extension at each end of a strip (cm) | 5 |
| Centre seal (1) or H seal (2) | 2 |
| Cartons | 20 |
| Tape roll length (m) | 50 |
A worked example
With the example inputs above, tape per carton (m) is 2.6. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Tape per carton (m) | 2.6 |
| Total tape (m) | 52 |
| Whole rolls | 2 |
How this is calculated
Tape per carton (m)
Two faces × [length + 2 × extension +, for H seal, 2 × (width + 2 × extension)], divided by 100.
Total tape (m)
Tape per carton × carton count.
Whole rolls
Round up total tape ÷ roll length.
Symbols and units
- a
- Carton length (cm)
- b
- Carton width (cm)
- c
- Tape extension at each end of a strip (cm)
- d
- Centre seal (1) or H seal (2)
- e
- Cartons
- f
- Tape roll length (m)
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
Seals both the top and bottom. Centre seal uses one lengthwise strip per face. H seal adds two crosswise strips per face. Each strip gets the entered extension at both ends. Does not include waste, rework or tape stretch.
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?
Tape per carton (m); Total tape (m); Whole rolls. 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: Seals both the top and bottom. Centre seal uses one lengthwise strip per face. H seal adds two crosswise strips per face. Each strip gets the entered extension at both ends. Does not include waste, rework or tape stretch.
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: geometric formulas and arithmetic ↗
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.
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