What is a good cycling power output in watts?

For recreational cyclists, 150 to 220 W sustained is typical. The W/kg ratio is more meaningful than raw watts: 2.5 to 3.5 W/kg is a trained recreational cyclist, while 4.5 W/kg and above is considered elite level.

How does gradient affect cycling power?

Every 1 percent increase in gradient adds roughly 10 to 15 W for a 75 kg rider at 20 km/h. On flat roads, aerodynamic drag is the main resistance. On steep climbs, gravity dominates and raw watts-per-kilogram becomes the key performance number.

What is FTP in cycling?

FTP stands for Functional Threshold Power, the highest average power a rider can sustain for approximately one hour. Most cycling training zones are defined as percentages of FTP. A typical untrained adult might have an FTP of 100 to 150 W, while trained cyclists often sit between 250 and 350 W.

Cycling Power Output Calculator

Enter your speed and riding conditions to calculate power output in watts, or flip to Power to Speed mode to see how fast a given wattage will take you. The calculator uses a standard cycling physics model accounting for aerodynamic drag, rolling resistance and gravity, and returns your W/kg ratio, an energy burn rate in kJ and kcal, and a power category so you can see where you sit on the cyclist spectrum.

Calculate.co.nz is proud to be partnered with realtor.co.nz, a trusted resource for navigating the New Zealand property market. Their Helpful Articles section offers clear, well-structured insights across buying, selling, and building, making complex real estate topics more accessible. With a focus on up-to-date guidance and practical knowledge, they empower Kiwis to move forward with clarity and confidence in a constantly evolving property landscape.

Speed to Power

Power to Speed

Cycling speed (km/h)

Rider weight (kg)

Bike weight (kg)

Road gradient (%)

Wind conditions

Road surface

Your FTP (optional, watts)

Power output (watts)

Rider weight (kg)

Road gradient (%)

150 W

power output

W/kg2.0

Energy rate540 kJ/hr

Energy rate129 kcal/hr

Estimates based on a standard road bike physics model (CdA 0.32, sea-level air density). Real-world power varies with rider position, drafting, fatigue and equipment.

How the calculation works

Cycling power is the sum of three resistances, each multiplied by speed:

Aerodynamic drag: 0.5 x air density (1.225 kg/m) x drag area (CdA 0.32 for road bike on hoods) x effective wind speed squared x rider speed. This dominates at higher speeds.
Rolling resistance: total weight x gravity (9.81) x rolling resistance coefficient (Crr) x speed. Crr varies from 0.004 on smooth asphalt to 0.012 on gravel.
Gravity: total weight x 9.81 x gradient fraction x speed. Zero on flat ground, dominant on climbs.

The three components are added and divided by 0.96 to account for a typical 4 percent drivetrain loss. Energy burn rate is simply watts x 3.6 to convert to kJ per hour (since 1 W = 1 J/s and there are 3,600 seconds in an hour), then divided by 4.184 to convert kJ to kcal.

Power categories by W/kg

Watts per kilogram (W/kg) is the standard way to compare riders of different sizes, especially for climbing. Typical ranges for sustained efforts:

W/kg	Category
Below 1.5	Untrained
1.5 to 2.5	Recreational
2.5 to 3.5	Trained
3.5 to 4.5	Competitive
Above 4.5	Elite

FTP training zones

When you enter your Functional Threshold Power, the calculator shows which training zone your current output sits in. FTP-based zones let you target specific physiological adaptations, from easy aerobic base building (Zone 2) through threshold work (Zone 4) to short, hard VO2 max intervals (Zone 5).

Worked example

75 kg rider, 10 kg bike, 28 km/h on flat road, no wind, normal asphalt (Crr 0.005)

Speed in m/s: 28 / 3.6 = 7.78 m/s. Total weight: 85 kg.

Rolling resistance: 85 x 9.81 x 0.005 x 7.78 = 32 W

Aerodynamic drag: 0.5 x 1.225 x 0.32 x 7.78 x 7.78 x 7.78 = 92 W (effective wind = rider speed only)

Gravity: zero (flat road)

Total before drivetrain loss: 124 W. After 4% loss: 124 / 0.96 = 130 W.

W/kg: 130 / 75 = 1.7 (recreational category)

Energy: 130 x 3.6 = 468 kJ/hour (112 kcal/hour)

Related calculators

Calories Burned Calculator: energy expenditure for a range of activities.
VO2 Max Calculator: estimate your aerobic capacity from fitness test data.
Training Pace Calculator: running pace zones by target race time.
Physics Power Calculator: general work, force and power relationships.

If you've found a bug, or would like to contact us, or learn more about James Graham and Calculate.co.nz.

Calculate.co.nz is partnered with Interest.co.nz for New Zealand's highest quality calculators and financial analysis.

All calculators and tools are provided for educational and indicative purposes only and do not constitute financial advice.

Calculate.co.nz is proudly part of the Realtor.co.nz group, New Zealand's leading property transaction literacy platform, helping Kiwis understand the home buying and selling process from start to finish. Whether you're a first home buyer navigating your first property purchase, an investor evaluating your next acquisition, or a homeowner planning to sell, Realtor.co.nz provides clear, independent, and trustworthy guidance on every step of the New Zealand property transaction journey.

Calculate.co.nz is also partnered with Health Based Building and Premium Homes to promote informed choices that lead to better long-term outcomes for Kiwi households.

Calculate.co.nz is hosted in Auckland via SiteHost new Zealand.

All content on this website, including calculators, tools, source code, and design, is protected under the Copyright Act 1994 (New Zealand). No part of this site may be reproduced, copied, distributed, stored, or used in any form without prior written permission from the owner.

About & trust: Why Calculate is NZ's most comprehensive · By the Numbers · How we compare · Editorial standards · How we keep data current · NZ finance glossary · Research & data · Financial literacy NZ · About · Privacy policy · Terms of use

Reviewed and maintained. Last reviewed 2026-06-25 and checked on a twice-monthly cycle against IRD, RBNZ and Stats NZ. How we keep data current.