THE NUMBERS, EXPLAINED
How to use this calculator.
Scales a measured sample using the same strand count and stitch style. Skein length must represent usable thread at that strand count; colour-by-colour waste needs separate samples.
Start with your inputs
Enter sample thread used (m), sample stitch count, design stitch count, reserve (%), usable skein length (m). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Sample thread used (m) | 2 |
| Sample stitch count | 100 |
| Design stitch count | 1000 |
| Reserve (%) | 20 |
| Usable skein length (m) | 8 |
A worked example
With the example inputs above, estimated thread (m) is 24. Change the inputs to explore your own scenario.
Putting the example numbers into the formula
Estimated thread (m)
(2) ÷ (100) × (1000) × (1+(20) ÷ 100) = 24
| Result | Example answer |
|---|---|
| Estimated thread (m) | 24 |
| Skeins | 3 |
How this is calculated
Estimated thread (m)
a ÷ b × c × (1+d ÷ 100)
Skeins
roundUp(a ÷ b × c × (1+d ÷ 100) ÷ e)
Symbols and units
- a
- Sample thread used (m)
- b
- Sample stitch count
- c
- Design stitch count
- d
- Reserve (%)
- e
- Usable skein 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”.
Calculation steps and notation
roundUp(x) rounds up to the next whole number. Values within two floating-point rounding units of an integer are treated as that integer.
Assumptions and limits
Scales a measured sample using the same strand count and stitch style. Skein length must represent usable thread at that strand count; colour-by-colour waste needs separate samples.
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?
Estimated thread (m); Skeins. 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: Scales a measured sample using the same strand count and stitch style. Skein length must represent usable thread at that strand count; colour-by-colour waste needs separate samples.
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: algebra and proportional reasoning ↗
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 →