THE NUMBERS, EXPLAINED
How to use this calculator.
Supported damage outline is rectangular and patch is axis-aligned; overlap is chosen by you. No assessment of repair durability or grain compatibility.
Start with your inputs
Enter rectangular damage width (mm), rectangular damage height (mm), chosen patch overlap on each side (mm), usable hide width (mm), usable hide height (mm). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Rectangular damage width (mm) | 40 |
| Rectangular damage height (mm) | 30 |
| Chosen patch overlap on each side (mm) | 10 |
| Usable hide width (mm) | 100 |
| Usable hide height (mm) | 80 |
A worked example
With the example inputs above, patch cut width (mm) is 60. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Patch cut width (mm) | 60 |
| Patch cut height (mm) | 50 |
| Patch area (square mm) | 3,000 |
| Fits supplied hide rectangle | Yes |
How this is calculated
Patch cut width (mm)
Extend both sides by overlap.
Patch cut height (mm)
Extend top and bottom by overlap.
Patch area (square mm)
Multiply cut dimensions.
Fits supplied hide rectangle
Compare patch dimensions with usable hide.
Symbols and units
- a
- Rectangular damage width (mm)
- b
- Rectangular damage height (mm)
- c
- Chosen patch overlap on each side (mm)
- d
- Usable hide width (mm)
- e
- Usable hide height (mm)
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
Supported damage outline is rectangular and patch is axis-aligned; overlap is chosen by you. No assessment of repair durability or grain compatibility.
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?
Patch cut width (mm); Patch cut height (mm); Patch area (square mm); Fits supplied hide rectangle. 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: Supported damage outline is rectangular and patch is axis-aligned; overlap is chosen by you. No assessment of repair durability or grain compatibility.
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 →