THE NUMBERS, EXPLAINED
How to use this calculator.
One endband with two alternating colour allocations. Total stitches round up and first-colour stitches round to nearest integer; both colour threads include their own allowance.
Start with your inputs
Enter spine width (mm), endband stitch pitch (mm), measured thread use per stitch (mm), first colour stitch share (%), starting-finishing allowance per colour (mm). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Spine width (mm) | 30 |
| Endband stitch pitch (mm) | 2 |
| Measured thread use per stitch (mm) | 10 |
| First colour stitch share (%) | 60 |
| Starting-finishing allowance per colour (mm) | 20 |
A worked example
With the example inputs above, endband stitch count is 15. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Endband stitch count | 15 |
| First-colour thread (mm) | 110 |
| Second-colour thread (mm) | 80 |
How this is calculated
Endband stitch count
Round spine width divided by stitch pitch upward.
First-colour thread (mm)
Allocate first-colour stitches and add its allowance.
Second-colour thread (mm)
Use the remaining stitches and add second-colour allowance.
Symbols and units
- a
- Spine width (mm)
- b
- Endband stitch pitch (mm)
- c
- Measured thread use per stitch (mm)
- d
- First colour stitch share (%)
- e
- Starting-finishing allowance per colour (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
One endband with two alternating colour allocations. Total stitches round up and first-colour stitches round to nearest integer; both colour threads include their own allowance.
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?
Endband stitch count; First-colour thread (mm); Second-colour thread (mm). 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: One endband with two alternating colour allocations. Total stitches round up and first-colour stitches round to nearest integer; both colour threads include their own allowance.
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.
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