A box says 0.1 ounce and shoppers read that as precision. It is not precision. It is the size of the step the display can show, and a scale can show tiny steps while being consistently wrong.
Resolution is what the screen can display
Resolution, or readability, is the smallest increment the readout moves in: one gram, a tenth of an ounce, a tenth of a gram. It describes the screen, not the sensor underneath it.
Accuracy is how close it is to true
Accuracy is the gap between what the scale says and what the object actually weighs. A scale reading in one-gram steps that is off by four grams is worse for bread dough than a coarse scale that is honest. Specification pages in a small-appliance catalog like https://peach-street.net/ list both when the maker is confident and only one when they are not.
Capacity fights precision
The same load cell cannot do eleven pounds and a tenth of a gram. High-capacity kitchen scales step in whole grams. Coffee scales that read to a tenth usually top out around six or seven pounds. Pick the job first.
The nickel test takes one minute
A United States nickel weighs five grams by mint specification. Ten of them should read fifty. If your scale says forty-six or fifty-four, you have found a real error and no amount of careful technique will fix it.
What makes a good scale read badly
- A soft or uneven surface, since a scale needs a flat, rigid counter.
- A bowl overhanging the platform and touching the countertop.
- A weak battery, which causes slow drift on long weighings.
- Moving it from a cold garage and using it right away.
- Leaning a hand or a spoon on the bowl while reading.
Drift, creep, and why numbers wander
Load cells are strain gauges, and strain gauges respond to temperature. A scale that just came indoors reads one number, then slides over a minute as it equalizes. Give it five minutes in the room first.
Linearity is the number nobody prints
A scale can be perfect at two pounds and off at eight ounces. Test at the weights you actually use. If you weigh coffee, test near twenty grams, not with a bag of sugar.
Calibration is not always available
Some scales accept a calibration weight and a button sequence. Many home models cannot be recalibrated at all, which makes an inaccurate one a replacement, not a repair.
Where each number actually matters
For flour and sugar, one-gram or tenth-ounce resolution is plenty. For espresso doses and yeast, finer steps genuinely help. For portioning meat, coarse is fine and capacity matters more.
How to read a spec sheet in ten seconds
Find the capacity, find the increment, and look for a stated tolerance. If tolerance is missing, assume two increments and test with nickels the day it arrives.