You see, Le Grand K is the most perfect kilogram on the planet. For weight measurements to mean anything, every scale has to be calibrated on the exact same standard, and that's where this ...

Even handling the model kilogram with your fingers will leave oil, changing its weight ever so slightly. It’s rarely removed from its enclosure, and never transported to other areas.

For over a century, the weight of a kilogram has been determined by a physical object, but that could change in 2018 under a new proposal that would base it on Planck's constant. While these tiny ...

How is your scale different? For the first 10 days, we tell them [the user] congratulations, you stepped on the scale. During those 10 days, we figure out how much their weight fluctuates.