I buy bubble wrap and tape rolls for my store in different lengths: how do I find the cheapest price per metre?

Example: three rolls of the same width

• A 10 m roll at 45: 4.50 per metre, 40.63% more expensive.
• A 50 m roll at 160: 3.20 per metre, the Best value.
• A small 200 cm roll at 12: 6.00 per metre, 87.5% more expensive.

The small roll is the cheapest at the till and close to double the price per metre. Choose per cm under Show cost and you read 0.045, 0.032 and 0.06, with the same percentages.

Why packing supplies deserve this check

They are a cost that repeats with every order and never shows clearly in the product price. Say you use about 300 metres of bubble wrap a year; that is your own figure, not a general one. The gap between 4.50 and 3.20 per metre is 1.30, so 1.30 × 300 = 390 a year, from a single packing material.

Steps

1. In the Unit-price comparison tool, enter each roll: its price, then its length, and pick m (metre) or cm (centimetre) as printed on the roll.
2. Do not convert centimetres to metres yourself; the tool does it internally.
3. Add up to six rolls or tapes from different suppliers.
4. Run separate comparisons per material: bubble wrap on its own, tape on its own.

What the comparison cannot see

• Width and thickness: a 50 cm wide roll is not a 100 cm wide roll. If widths differ, comparing per metre alone is unfair.
• Quality: a cheap tape that needs two wraps instead of one can cancel the saving.
• Minimum order and delivery: if the big roll comes with paid delivery, add it to the price before entering it.

Remember that packing affects shipping too: extra layers of bubble wrap make the carton bigger, and a bigger carton can push up the chargeable weight. Check that with the Volumetric shipping-weight calculator. And log packing purchases in the Expense summary generator to see what you spend on them each month.