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.
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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Professionally Built
Each bike is expertly tuned, 85% assembled, and ready to ride within minutes.
Watch Assembly Video
Safety First System
Kid-specific geometry, short-reach 2-finger brakes, and shorter cranks for confident, controlled riding.
Learn MoreFind 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
Polygon Premier 20 - Ultralight Kids Bike
Polygon Relic 20 - Kids Mountain Bike
Polygon Xtrada 20 - Kids Mountain Bike
Reid - Viper 20 inch Kids Bike
Reid - Tract Jr 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 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
What People 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
Find answers to common questions about our products and services.
Orders are generally dispatched within 48 hours from our warehouse. Delivery times vary by location: 2–5 business days to metropolitan areas, 5–10 days to regional areas and 7–12 days for remote parts of Australia. We ship across Australia and a tracking link is emailed once your order leaves the warehouse.
We offer a 30‑day hassle‑free return period. Unused bikes can be returned for a refund or store credit, and exchanges for a different size or colour are also possible. Returns are processed quickly so kids aren’t kept waiting.
Fit matters more than age. To get the best size:
- Measure your child’s inseam (inner leg length) by having them stand against a wall wearing their riding shoes, pressing a hardcover book up to their crotch, then measuring from the floor to the top of the book.
- Choose a bike that allows your child to sit with both feet flat on the ground; this builds confidence and safety.
- Balance bikes should have the saddle 1–3 cm below inseam; first‑pedal bikes should match inseam; experienced riders can raise the saddle 5–10 cm above inseam.
The tool lets you input inseam (and optionally height or age), then select your child’s riding ability and preferred terrain. It returns a wheel‑size recommendation and a list of suitable models. Beginners usually benefit from smaller wheels (e.g., 16″), while confident riders may size up.
Yes. Bikes arrive 85–90 % pre‑assembled. You only need to attach the handlebars, install the front wheel and adjust the seat; the process usually takes about 15 minutes. Tools and instructions are included.
Bikes are sold without helmets or accessories. However, BikesOnline sells certified helmets, lights, bells and other accessories/gear separately. Helmets meeting Australian standards are mandatory for all riders.
Yes. All BikesOnline kids’ bikes include a limited manufacturer’s warranty covering the frame, fork and components. BikesOnline provides resources for basic maintenance and recommends regular servicing at a local bike shop.
If a bike is listed as sold out, you can enter your email to receive a notification when pre‑orders open or when stock is replenished.
Lighter bikes are easier for kids to start, stop and control, which builds confidence. Heavy bikes can make learning more difficult and tiring. BikesOnline designs its kids’ bikes with lightweight frames and child‑specific geometry.
