# Component yarn planner

> Combine measured yarn requirements by material and color, then round whole balls once for each group.

- [Open tool](https://threadcabin.com/tools/component-yarn-planner)
- Start with the calculator. Formula, assumptions, and limits are available when you need them.

## Before you use this tool

Enter each component’s base length before reserve and assign its material/color group. Components in one group share the same package facts; different colors stay in different groups.

The tool combines lengths and rounds packages once per group, so leftovers cannot cover a different color.

## Formula and assumptions

For each group, add component lengths; multiply once by (1 + allowance ÷ 100); divide by label length and round up. Multiply whole balls by label length and mass. Enter lengths before allowance. Do not add a second reserve to an estimate that already includes one.

## Worked example

Group A: 120 m + 80 m = 200 m; with 10% reserve, 220 m requires three 100 m/50 g balls. Group B: 60 m with 10% reserve requires one separate 100 m/50 g ball. The groups cannot share their rounding surplus.

- [Yarn label anatomy: turn symbols and numbers into decisions](https://threadcabin.com/explore/15/yarn-label-anatomy-turn-symbols-and-numbers-into-decisions)

## Limits and rounding

Results are planning estimates from the values entered. Displayed decimals are rounded for craft use; whole materials and repeats round up where the method says so. Confirm gauge, material behavior, construction, and finished measurements before committing supplies.