USA
The perfect kids bike, direct to your door
One-stop kids' bike shop with sizing quiz, easy assembly, free 30-day returns, and best price guaranteed.
Professionally Built
Each bike is expertly tuned, 85% assembled, and ready to ride within minutes.
FREE 30-Day Return
If it's not the perfect fit, return it free within 30-days. Plus, we guarantee the best price - always.
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Safety First System
Kid-specific geometry, short-reach 2-finger brakes, and shorter cranks for confident, controlled riding.
Find the perfect kids bike
Take a quick quiz, and we'll recommend the right size and model.
Let's get started!
How would you like to measure your kid for their bike? Pick one option and click next to get started
What is your child's leg length?
What is your child's height?
with shoes on!
How old is your child?
Select age in years
Where will your child be riding most?
Smooth ground
Footpaths, bike paths, school ovals, and local parks
Adventure terrain
Bumpy parks, light trails, and uneven ground
Which best describes your child's riding skills?
Your recommended bikes
Based on your answers, here are the perfect bikes for your child:
Kids Bike Sizing Guide
Berg Biky Cross w-Handbrake - Balance Bike
Strider 12 Sport - Balance Bike
Reid - Girls Classic 16-inch Vintage Bike
Reid - Boys Classic 16 inch Vintage Bike
Reid - Explorer 12-inch Kids Bike
Reid - Explorer S 20-inch Kids Bike
Reid - Explorer 16-inch Kids Bike
Reid - Girls Vintage Balance
Polygon Premier 20 - Ultralight Kids Bike
Polygon Relic 20 - Kids Mountain Bike
Polygon Xtrada 20 - Kids Mountain Bike
Reid - Tract Jr 20 inch Kids Bike
Reid - Viper 20 inch Kids Bike
![Marin Bayview Trail 20 - Kids Mountain Bike [New]](http://bikesonline.com.au/cdn/shop/files/MarinBayviewTrail24-KidsMountainBike_lightblue.jpg?v=1758082646&width=400)
Marin Bayview Trail 20 - Kids Mountain Bike [New]
Reid - Impact 20 inch Kids Bike
Marin San Quentin 20 Jr - Kids Mountain Bike
Reid - Girls Classic 20 inch Vintage Bike
Ex Demo - Polygon Xtrada 20 - Kids Mountain Bike K1
Polygon Premier 20 Disc - Kids Urban Bike
Polygon Premier 20 Disc EVO - Kids Urban Bike
Polygon Premier 24 XC Disc - Kids Mountain Bike
Polygon Premier 24 XC Disc Evo - Kids Mountain Bike
Polygon Premier 24 XC - Kids Mountain Bike
Polygon Premier 24 - Ultralight Kids Bike
Polygon Siskiu D24 - Kids Mountain Bike
Polygon Siskiu D24 EVO - Kids Mountain Bike
Polygon Xtrada 24 - Kids Mountain Bike
Reid - Tract Jr 24 inch Kids Bike
Reid - Ladies Petite 24-inch Vintage Bike
Marin Alcatraz 24 - Kids Dirt Jump Bike
![Marin Rift Zone Jr - Kids Mountain Bike [New]](http://bikesonline.com.au/cdn/shop/files/Marin_Rift_Zone_Jr_lifestyle_main.jpg?v=1751406894&width=400)
Marin Rift Zone Jr - Kids Mountain Bike [New]
![Marin Bayview Trail 24 - Kids Mountain Bike [New]](http://bikesonline.com.au/cdn/shop/files/MarinBayviewTrail24-KidsMountainBike_red.jpg?v=1749882508&width=400)
Marin Bayview Trail 24 - Kids Mountain Bike [New]
Reid - Impact 24 inch Kids Bike
Marin San Quentin 24 Jr - Kids Mountain Bike
Reid - Tract Jr 26-inch Kids Bike
What Kids Are Saying
Gina E. Verified Buyer
Awesome Bike!! Happy kid!!
Amazing experience and overall quality!
Lars
It's really good! I love this bike. My favourite is the way that it jumps.
Keith D. Verified Buyer
Fantastic Value
This was my first time ordering a bike online, and the first that I've ever even partially assembled myself. But the packaging and videos made it easy.
Jennifer Verified Buyer
Great kids bike at a great price
Was looking for a great lightweight entry level bike for my twin boys. This so far has fit the bill. Like that it came in 2 different color options.
Kym W. Verified Buyer
I love it
The bike was really easy to put together. And really smooth to ride once you are done i love it so much. I am Darcy wurst and the bike is my early christmas present
Jarrod C. Verified Buyer
First big girl bike
We bought this bike for my daughter's 8th birthday. She's always had box store bikes that were heavy and cumbersome. She struggled to ride for very long at a time. She immediately loved this one.
Frequently Asked Questions
You can measure by height, age, or leg length — whichever is easiest for you. For the most accurate fit, use leg length, as it directly matches the bike’s standover height and ensures safe balance.
When you can’t measure leg length, height is the next best indicator of bike size. Age gives only a rough estimate since kids grow at different rates, so using height (or leg length if possible) will help you find the best fit.
Most 7-year-olds fit a 20-inch bike, depending on their height and leg length. Our Kids Bikes Ages 5–8 are great for confident riders learning gears and brakes.
It’s safer to choose the right fit now than buy one that’s too large. A bike that’s too big can make balancing harder.
When seated, your child should touch the ground with both feet and have a slight bend in their knees while pedalling.
Most kids outgrow their bikes every 2–3 years, depending on growth rate and usage. Choosing the right bike fit from our Kids Bikes Ages 9+ range helps extend the bike’s lifespan and ensures safe riding comfort.
