Mechanical keyboard switch weights and the difference you actually feel

Mechanical keyboard switch specs quote actuation force in grams (technically grams-force, but everyone drops the 'force'). It's the weight, in a standard test, that pushes the switch down to its activation point. Cherry MX Red is 45 g actuation, Brown 45 g with a tactile bump around 55 g peak, Blue 50 g with a click, Black 60 g, Clear 65 g, Green 80 g. Modern boutique switches range from about 35 g to 80 g.

The math nobody does

An average typist hits 250 characters per minute during real typing, so about 15,000 keypresses per hour. At 45 g per press that's 675 kg of vertical work per hour just to type. At 60 g it's 900 kg. That 225 kg per hour is your fingers, and it accumulates as fatigue in flexor tendons.

Why heavy exists

Heavier switches resist accidental keypresses. If you rest your fingers on the keys (a common typing style) light switches will bottom out and you'll type gibberish. Heavy switches let you rest fingers without activating. Programmers and writers often prefer heavier tactile switches; gamers who want fast repeated presses often prefer light linears.

Grams vs cN

Some manufacturers spec in centinewtons: 1 gf ≈ 0.98 cN, close enough to use interchangeably. A '45 cN' switch is a '45 g' switch. Topre capacitive switches are usually spec'd in grams (30, 45, 55) though they behave completely differently from MX-style — the force curve is more like a rubber dome than a spring.

Recap

Try a switch tester before buying a full board. 15 g difference in actuation is real and your hands know it after an hour.