How much yarn is left?
Use the original label length and weight to estimate the length remaining in the same yarn. Weigh only the yarn, without its label or core.
Use the total length printed on the yarn label.
Use the full yarn-only weight printed on the label.
Weigh the yarn alone in the shared unit selected above.
Estimated yarn remaining
Approximately 35% of the original length.
Original length × remaining weight ÷ original weight. Use the same yarn and exclude labels, bobbins, cores and containers from the remaining weight.
This assumes the yarn’s length per unit of weight is consistent. Allow a margin for scale error and variation; it cannot guarantee enough yarn to finish a pattern.
Values are not saved. Reloading or closing this page restores the worked example.
Worked example: 400 yards on a 100-gram label
Suppose the label says the full skein contained 400 yards at 100 grams. After using part of it, the remaining yarn alone weighs 35 grams. The estimate is 400 × 35 ÷ 100 = 140 yards remaining.
Enter 400 for original length, 100 for original weight and 35 for remaining weight. Keep both weight values in the same unit—grams with grams or ounces with ounces. The length selection labels the result; it does not convert an entered number between yards and meters.
How to interpret the estimate
The calculation assumes the remaining material is the same yarn as the original label and that length is distributed in proportion to weight. Weigh only the yarn: remove the paper label, cone, bobbin, bag or other holder. Scale rounding, moisture, joins and manufacturing variation can shift the result, so leave a margin before relying on the estimate to finish a row, repeat or project.
Use Download estimate to keep a plain-text record with the inputs, formula and assumptions. The page itself does not save the values: reloading or closing it restores the worked example, and nothing syncs to another device.
Keep the details with your yarn.
Save the yarn name, dye lot, original length and original weight. Our yarn storage guide explains how to keep those details with the cake. For equipment choices, return to the yarn winder guide.
Updated October 4, 2026.