Frequently asked questions

Measure their inseam and match it to the bike's minimum saddle height. As a starting point: a 10 to 18 inch inseam fits a 12-inch wheel, 14 to 19 inches fits 14-inch, 15.5 to 25 inches fits 16-inch, 18.3 to 28 inches fits 20-inch, and 26 to 32 inches fits 24-inch.

Stand them against a wall in the shoes they will ride in, raise a hardcover book spine-up between their legs with the pressure a saddle would apply, mark the wall at the top of the spine, and measure from the floor to the mark.

Because the manufacturers disagree wildly about age. For a five-year-old, woom's 16-inch needs a 19.1 inch inseam, Prevelo's fits from 15.5 inches, and Guardian publishes a 16.25 inch minimum leg length. One measurement resolves all three.

No. A bike a child cannot put their feet down on gets avoided for a season, and an unridden bike costs the same as a ridden one. Buy the size that fits now and resell it — good kids bikes hold their value.

For learning to ride, yes. A balance bike teaches the child to steer into a lean, which is what keeps a two-wheeler upright. Training wheels prevent the bike leaning, so that skill never gets practiced.

When they can sit on the lowest saddle setting with both feet flat and walk the bike forward. For most children that is between 18 months and two and a half years.

When the child can glide with both feet up for around ten seconds, steer deliberately while gliding, and start and stop confidently. Age is not the signal.

Under about a third of the child's body weight. For a typical five-year-old at 39.8 lb that means roughly 13 lb, which rules out most mass-market bikes — the 16-inch examples we researched run from 12.1 lb to 21.16 lb.

Steel frames, adult-scale components, a coaster brake hub and extras like training wheels and kickstands, all to hit a low price. The result can be a bike that weighs half what the child does.

The measurable benefit is about 8 lb of weight, brakes a small hand can use, and published fit data. For a child who rides regularly that changes the experience; for occasional driveway use it does not.

Hand brakes. Every bike your child rides afterwards will have them, and a coaster brake blocks backpedaling to set the pedal position for a start.

When their usual route has hills they grind up or push up — usually somewhere between six and eight. On flat ground a single speed is lighter, cheaper and has nothing to adjust.

Helmet sizes are head circumference, not age. Measure around the head about an inch above the eyebrows: toddler sizes run roughly 45 to 50 cm, child sizes 48 to 54, youth 50 to 57.

Yes. The CPSC standard requires helmets intended for children up to age five to provide extended head coverage, so a helmet certified only for age 5 and older is the wrong product for a toddler.

It addresses rotational force in angled impacts and is genuine engineering rather than marketing. It matters less than whether the helmet fits and gets worn every ride.

After any impact where the head struck something, as soon as it stops fitting, or when the shell, foam or straps show damage. Helmets protect by crushing, and crushed foam does not recover.

No, and every product card says so. We research published manufacturer specs, link the page we read them on, and do the fit and weight arithmetic in public. Where that is not enough, we say what we would check in person.

Because we have no first-party testing data that would justify a score, and no customer reviews to quote. Inventing either would be fabrication, so we publish neither.

Prices move. A number typed into an article a year ago is confidently wrong, which is worse than silent. Prices here render from a live data layer with the date attached, or the button says check price.

Affiliate commission on some links, disclosed above the first link on every commercial page. Several bikes we rank highest — woom, Guardian, Prevelo — pay us nothing, because we have no affiliate relationship with them.