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Home > Guides > Weighing without a scale
Step on a bathroom scale holding the package, then step on without it, and subtract: the difference is the package weight. It is accurate enough for most shipping labels. For light parcels under a kilogram or so, use a kitchen scale, or compare the parcel against something of known weight, like a one-litre water bottle (about a kilogram).
More accurate than most people think, but less than they fear. Carriers weigh parcels on their own equipment as they move through the system, and if your declared weight is under the real one, the carrier bills a weight correction: either to you, if you bought the label on an account, or as a postage-due charge that can stall the parcel. Being off by a little on a home scale is rarely the problem; being off by a kilogram because you guessed is.
| Method | Typical accuracy | Best for |
|---|---|---|
| Bathroom scale, tare method | Within about half a kilogram, if the scale is decent | Parcels over 2 kg where rounding up is fine |
| Kitchen scale | Within a few grams | Light parcels, mailers, anything under 5 kg |
| Known-weight comparison | Within half a kilogram if you are careful | A quick ballpark when no scale is handy |
| Carrier scale at drop-off | Exact | When you buy the label at the counter anyway |
The practical rule: round up, not down. If your bathroom scale says 3.4 kg, declare 4 kg on a weight-based label. The small overpay is cheaper than a correction, and on a flat-rate label it does not matter at all.
Not for the price, but it still has to be declared and it still has a ceiling. LetterAgent labels are flat-rate Xpresspost, so the quoted price does not change with weight, but the parcel must be 5 kg or under. A bathroom-scale reading is plenty accurate for that check: you just need to know whether you are safely under the limit, not the exact gram count. If you are anywhere near 5 kg, use a kitchen scale to confirm before you buy the label.
Weight is only half the pricing story. Carriers also charge by dimensional (volumetric) weight: a big, light box can be billed as though it were heavier than it is. You cannot fix that with a scale, but you can fix it with a smaller box. If your parcel is light but bulky, the box size matters more than the bathroom-scale number. Measure the box with a tape measure and compare carriers' size bands before you buy.
Ready to ship it? Get a shipping label with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and get your label.
LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
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