Rolling Resistance Calculator

Estimate the rolling resistance of any vehicle

Calculate rolling resistance using presets, known wheel/surface friction coefficient, or a given friction coefficient (μ).

Last updated: December 21, 2025

CreatorFrank Zhao

Find the rolling resistance

Calculate from...

presetsknown wheel/surface friction coeff.a given friction coefficient (μ)

Presets

Gravity

More info

m/s²

Mass of the vehicle

More info

Result

Rolling resistance

More info

📚

Quick Navigation

Rolling resistance is the quiet force that keeps “stealing” energy from your motion — whether you’re driving to work or trying to hold a steady pace on a bike. This guide explains what the calculator is doing, how to use it in minutes, and how to interpret the result in the real world.

→Rolling resistance basics
→Tire rolling resistance
→What causes it?
→How to use this calculator
→Rolling resistance vs. drag
→Car vs. bicycle
→Real-world examples
→Tips & best practices
→Formulas & variables
→FAQs
→Limitations
→Summary

🛞

Rolling resistance — basics

Rolling resistance is the force that resists motion when a wheel rolls on a surface. It’s not “one big thing” — it’s the combined energy loss from small deformations in the tire, the road, and even the wheel system.

🔍 A practical way to think about it: if your vehicle needs extra push even on a flat road, part of that effort is used to overcome rolling resistance.

This calculator helps you estimate the rolling resistance force $F_{rr}$ using either a preset rolling resistance coefficient (common wheel/surface combinations), a “given” friction-style coefficient $\mu$ , or a rolling friction coefficient $b$ combined with wheel radius $r$ .

What problem does it solve?

Estimate how “hard” it is to keep rolling on a given surface.
Compare two tires/surfaces quickly (e.g., rough road vs. smooth asphalt).
Turn “spec sheet coefficients” into a real force you can interpret.

Who is it for? Drivers who are curious about low-rolling-resistance tires, cyclists who care about watts, engineering students who want a clean physics estimate, and anyone comparing surfaces (asphalt, concrete, rails, sand…).

🚗

Tire rolling resistance

In cars and bikes, rolling resistance is usually talked about in terms of tires — because tires are the easiest thing to change. Switching to a different tire model, changing pressure, or moving from smooth asphalt to rough pavement can noticeably change $F_{rr}$ .

💸

Cost & efficiency

Lower rolling resistance can reduce the energy needed to maintain speed — which may translate into small fuel or battery savings.

🏁

Performance

In racing and time trials, even a small reduction in $F_{rr}$ can mean a real watts savings.

💡

Friendly reminder: rolling resistance is not “a tire-only property.” Any rolling object on any surface has rolling resistance — tires on asphalt, steel wheels on rails, even wheels on sand.

🧩

What is rolling resistance caused by?

The simplest physics model treats rolling resistance like a friction-style force proportional to the normal force $N$ :

Core relationship

F_{rr} = \mu\,N

Here $\mu$ is an effective rolling resistance coefficient and $N$ is the normal force (roughly the vehicle weight on level ground).

In real life, the coefficient can change with tire pressure, temperature, speed, road texture, and internal tire construction. That’s why the calculator offers presets: they’re a practical starting point when you don’t want to hunt down a perfect $\mu$ value.

Common causes in plain English:

Tire deformation (the tire “squishes” and doesn’t return all energy).
Surface texture (rough pavement makes the tire work harder).
Mechanical losses (bearings, wheel alignment, small rubbing contacts).

🧮

How to calculate rolling resistance using this calculator

You can use this tool in three ways. If you’re not sure which one to pick, start with Presets — it’s the fastest way to get a reasonable estimate.

Choose a calculation mode

Pick Presets, Known wheel/surface rolling friction (uses $b$ and $r$ ), or Given $\mu$ .

Enter mass and gravity

The normal force on level ground is approximately $N = m g$ . The calculator lets you switch units (kg, lb, tons…) and change $g$ if needed.

Read the rolling resistance force

The output is the rolling resistance force $F_{rr}$ (in N, lbf, etc.). Higher values mean you need more push (or more power) to maintain speed.

Compare scenarios (this is where it gets useful)

Try the same mass with two different coefficients, or switch presets. The difference in $F_{rr}$ is often the quickest way to judge whether a change is worth it.

What you’ll see in the calculator

A dropdown with presets (bike, car, truck, rail, sand…)
Inputs for $m$ , $g$ , and either $\mu$ or $b$ and $r$
An output field for $F_{rr}$ with unit conversion

Worked example (car on asphalt)

Suppose a car has mass $m = 1500\ \text{kg}$ and you use a typical asphalt preset coefficient $\mu = 0.02$ with $g = 9.81\ \text{m/s}^2$ .

N = m g = 1500 \cdot 9.81 = 14715\ \text{N}

F_{rr} = \mu N = 0.02 \cdot 14715 \approx 294.3\ \text{N}

Interpretation: you need about $294\ \text{N}$ of forward force just to cancel rolling resistance on level ground (ignoring air drag, drivetrain losses, hills, etc.).

Worked example (bike watts estimate)

A rider + bike has total mass $m = 85\ \text{kg}$ . On smooth asphalt, you might use $\mu = 0.004$ . First compute $F_{rr}$ , then estimate rolling-resistance power with $P = F_{rr} v$ .

N = m g = 85 \cdot 9.81 \approx 833.5\ \text{N}

F_{rr} = \mu N = 0.004 \cdot 833.5 \approx 3.33\ \text{N}

v = 25\ \text{km/h} \approx 6.94\ \text{m/s}

P = F_{rr}v \approx 3.33 \cdot 6.94 \approx 23.1\ \text{W}

Interpretation: around $23\ \text{W}$ goes into rolling resistance at that speed (again, ignoring air drag). If you’re comparing tires, it’s the difference in watts that’s most actionable.

Want the drag side of the story too? Pair this with our Free Fall Air Resistance Calculator to get a feel for how strongly drag can scale with speed.

🌬️

Rolling resistance and drag: how to reduce fuel consumption?

To keep a steady speed on flat ground, your vehicle needs to overcome multiple losses. Two big ones are rolling resistance $F_{rr}$ and aerodynamic drag (often written as $F_d$ ).

A simple takeaway

Rolling resistance tends to scale with weight (through $N \approx mg$ ), so heavier vehicles pay more.
Drag tends to grow strongly with speed (that’s why high-speed driving is so fuel-hungry).

✅

How to actually lower your total energy use:

Keep tires properly inflated (under-inflation usually increases rolling losses).
Reduce unnecessary load (because $F_{rr} \propto m$ in the basic model).
At highway speeds, lowering speed often beats any tire upgrade.

If you’re trying to decide whether “low rolling resistance” tires make sense, focus on what you can actually measure: the difference in $F_{rr}$ (and therefore in required power) between two scenarios.

🚴

Car and bicycle rolling resistance

For a car, rolling resistance is real — but at higher speeds, aerodynamic drag often becomes the bigger piece of the puzzle. For a bicycle at typical city speeds, rolling resistance can feel surprisingly important because the total available power is much smaller.

Why bikes “feel it” more

A cyclist may sustain something like $150\text{–}250\ \text{W}$ for a long effort. If rolling resistance changes by $20\ \text{W}$ , you notice.

Why cars are different

Cars have much more power available, and at highway speeds drag can dominate. Rolling resistance still matters, but it’s rarely the only lever.

If you’re comparing upgrades, this is a good workflow: estimate $F_{rr}$ here, then check your broader forces with our Friction Calculator when you want to reason about traction limits or other friction scenarios.

🧪

Real-world examples / use cases

1) Compare two car tires (same vehicle)

Scenario: Same car, same road, you’re deciding between a standard tire and a low-rolling-resistance model.

Inputs: $m = 1500\ \text{kg}$ , $g = 9.81\ \text{m/s}^2$ , and compare $\mu_1 = 0.02$ vs $\mu_2 = 0.0125$ .

\Delta F_{rr} = (\mu_1-\mu_2) m g

= (0.02-0.0125) \cdot 1500 \cdot 9.81

\approx 110.4\ \text{N}

How to use it: That difference is the “force savings” on flat ground. To turn it into a rough power estimate at a speed $v$ , use $\Delta P \approx \Delta F_{rr} v$ .

2) Bike: rough road vs smooth road

Scenario: You ride the same route, but part of it is chipseal (rough) and part is smooth asphalt.

Inputs: $m = 80\ \text{kg}$ , $g = 9.81\ \text{m/s}^2$ , and $\mu_{rough} = 0.008$ vs $\mu_{smooth} = 0.004$ .

\Delta F_{rr} = (0.008-0.004) \cdot 80 \cdot 9.81 \approx 3.14\ \text{N}

v = 30\ \text{km/h} \approx 8.33\ \text{m/s}

\Delta P \approx 3.14 \cdot 8.33 \approx 26.2\ \text{W}

How to use it: A ~ $26\ \text{W}$ difference is noticeable for many riders — especially in long efforts.

3) Rail: why steel-on-steel is efficient

Scenario: You’re estimating the rolling resistance force of a train.

Inputs: $m = 200{,}000\ \text{kg}$ , $g = 9.81\ \text{m/s}^2$ , and $\mu = 0.0015$ .

F_{rr} = \mu m g = 0.0015 \cdot 200{,}000 \cdot 9.81 \approx 2943\ \text{N}

How to use it: The force is large in absolute terms, but the coefficient is tiny — that’s part of why rail transport is energy-efficient.

4) “My ride feels slow” sanity check

Scenario: Your bike suddenly feels harder to push on flat ground.

Inputs: keep $m$ and $g$ fixed, and test what happens if $\mu$ doubles.

F_{rr} \propto \mu \Rightarrow \mu\ \text{doubles} \Rightarrow F_{rr}\ \text{doubles}

How to use it: If your result changes dramatically with small coefficient changes, it’s a hint that tire pressure, rubbing brakes, or bearing issues might be worth checking.

🛠️

Tips & best practices

Use presets as a baseline, then do “what if” comparisons. The most useful number is often $\Delta F_{rr}$ .
Keep units consistent when comparing scenarios. If you switch mass units (kg ↔ lb), double-check that the number is still the same physical mass.
If you’re estimating watts, remember $P = F v$ . A small force difference becomes more important at higher speeds.
Don’t confuse “rolling resistance” with “traction.” Traction is about maximum usable friction before slipping; rolling resistance is about energy loss while rolling.

Common mistake: assuming tire size alone changes rolling resistance. In this simplified model, the big drivers are coefficient and normal force $N$ — which usually means coefficient and weight.

📐

Calculation method / formula explanation

The calculator uses a simple and widely used approximation: rolling resistance is proportional to the normal force. On level ground, the normal force is approximately $N \approx m g$ .

Main formula

F_{rr} = \mu N

N \approx m g

\Rightarrow\quad F_{rr} \approx \mu m g

Variable meanings

$F_{rr}$ : rolling resistance force (opposes motion)
$\mu$ : effective rolling resistance coefficient (preset or entered)
$N$ : normal force (roughly the weight on level ground)
$m$ : mass of the vehicle
$g$ : gravitational acceleration

If you use the “known wheel/surface rolling friction coefficient” mode, the calculator first converts the rolling friction coefficient $b$ and radius $r$ into an effective coefficient:

Wheel/surface mode

\mu = \frac{b}{r}

F_{rr} = \left(\frac{b}{r}\right) m g

❓

Frequently asked questions (FAQs)

Is rolling resistance the same as friction?

They’re related, but not identical. The calculator uses a friction-style model $F_{rr} = \mu N$ , but the underlying cause often comes from deformation and energy loss, not just sliding friction.

Does rolling resistance depend on tire size?

Not directly in this simplified model. Here, $F_{rr}$ is driven mainly by the coefficient $\mu$ and the normal force $N \approx mg$ .

Why does weight matter so much?

Because the normal force grows with weight. If $N \approx mg$ , then $F_{rr} \approx \mu m g$ — so doubling $m$ roughly doubles $F_{rr}$ .

What’s a “good” rolling resistance coefficient?

It depends on the wheel and surface. As a rough mental range, many common cases fall between $\mu \approx 0.001\text{–}0.03$ . Sand can be much higher.

How do I convert the result into watts?

Use $P = F_{rr} v$ where $v$ is speed in $\text{m/s}$ . The calculator outputs $F_{rr}$ ; multiply by your speed to estimate rolling-resistance power.

Why do presets sometimes feel “off”?

Presets are representative values — real $\mu$ can shift with pressure, temperature, tire compound, road texture, and speed. Treat presets as a solid starting estimate, not a lab measurement.

Can I use this for hills?

The calculator focuses on rolling resistance on level ground. On a slope, you also need to account for the component of gravity along the slope. Rolling resistance still exists, but total required force changes.

Can this replace real-world testing?

It’s best for comparison and estimation. For high-stakes decisions (racing setups, engineering design), use this as a first-pass model, then validate with measurements.

⚠️

Limitations / disclaimers

This calculator provides an estimate based on simplified relationships such as $F_{rr} = \mu N$ and $N \approx m g$ .

Real rolling resistance coefficients can vary with speed, pressure, temperature, and surface roughness — your true value may differ.
The model does not include drivetrain losses, wind, bearing drag details, or road slope.
This is educational content and should not replace professional engineering advice when safety or compliance is involved.

✅

Summary: what you should take away

Rolling resistance is an opposing force $F_{rr}$ that “steals” energy as you roll.
The basic estimate is $F_{rr} \approx \mu m g$ on level ground.
Presets give you a quick starting coefficient; comparisons (differences) are usually more useful than any single absolute number.
To translate force into power at speed, use $P = F_{rr} v$ .
For fuel savings, don’t forget drag: at higher speeds, aerodynamics can matter more than rolling resistance.

Related Calculators

Trajectory Calculator

Have a look at the flight path of the object with this trajectory calculator.

Try Now

Free Fall Calculator

Calculate free fall parameters including gravitational acceleration, drop height, fall duration, and impact velocity. Supports bidirectional LRU solving with unit conversions.

Try Now

Free Fall with Air Resistance Calculator

Calculate free fall with quadratic air drag, including terminal velocity, fall time, maximum velocity, and drag force. Supports air resistance coefficient calculation from object properties.

Try Now

Projectile Range Calculator

Calculate the horizontal range of a projectile based on velocity, angle, and initial height. Supports bidirectional calculation with multiple unit systems.

Try Now

Projectile Motion Calculator

Calculate projectile trajectory parameters including launch velocity, angle, distance, maximum height, and flight time with bidirectional solving.

Try Now

Maximum Height Calculator – Projectile Motion

Use this maximum height calculator to figure out what is the maximum vertical position of an object in projectile motion.

Try Now