RUBBERDOT

Anti-Slip Friction & Coefficient Estimator

Will it slide? Enter the weight and the coefficient of friction to see the sideways force the feet resist, the steepest slope it stays put on, and — if you add a push force — whether it slips.

Weight pressing the feet onto the surface.
Rubber on a clean hard floor is often 0.6–0.9; waxed or dusty is much lower.
A sideways force trying to slide it. Leave blank to skip.
Total footprint of the pads, to see the contact pressure.

Will it slide?

Normal force
98.1 N
Resists up to
58.8 N
= sideways
6 kg
Max incline
31°
Coefficient needed
0.41

✓ It stays put — the grip beats the push at this coefficient.

Grip is weight times coefficient

Whether a rubber-footed object holds comes down to a simple balance. Pressing it down is its weight; holding it in place is friction — the coefficient between the feet and the floor, times that weight. As long as the sideways force stays under that limit, nothing moves.

That’s why the surface matters so much. Rubber on clean tile grips hard, but the same feet on a dusty, waxed, or wet floor can let go, because the coefficient collapses. If something has started sliding, the fix is usually more weight, a grippier pad, or a cleaner surface — and this tool shows you how much of each you need.

Frequently Asked Questions

What makes something slide or stay put?

Friction. The most sideways force an object resists before it moves is the coefficient of friction multiplied by the weight pressing it down. If a push exceeds that, it slides; if not, it holds. Heavier objects and grippier surfaces resist more.

What is a typical coefficient of friction for rubber?

Rubber on a clean, dry hard floor is often around 0.6 to 0.9, which is why rubber feet grip so well. But a waxed, wet, dusty, or greasy surface can drop the coefficient dramatically, and that's usually why something that used to stay put starts sliding.

Does a bigger contact area give more grip?

For classic dry friction, no — the holding force depends on the weight and the coefficient, not the area. Area still matters in practice: it sets the contact pressure, which affects how a soft pad bites into carpet pile or conforms to a rough floor. This tool reports that pressure when you enter an area.

How steep a slope can it sit on before sliding?

An object stays put until the slope angle passes the arctangent of the coefficient of friction. At a coefficient of 1.0 that's 45 degrees; at 0.6 it's about 31 degrees. The tool shows this maximum stable incline for your coefficient.

Estimates only. Real friction varies with the exact surfaces, moisture, and contamination — test in place.