KidsSizes.co.uk

Sizes for an 8 year old

Clothes, shoes, bike, scooter, helmet and bedtime sizes for an 8 year old, all on one page and taken from UK retailers' own charts.

Checked against UK retailer charts on 18 October 2026.

Clothes
Usually 8–9 years (cut for up to 134 cm at Boden)
Shoes
Typically around UK 12.5 to 2, but measure their feet
Bike
20" or 24" wheels
Bike helmet
Juniors size, about 52–59 cm head circumference
Duvet
4.5–9 tog depending on season
School uniform
Chest about 28", waist about 24"

Clothes

UK shops label children's clothes by age but cut them to a height. A label like "8–9 years" fits a child from their 8th birthday up to their 9th, so an 8 year old is usually in 8–9 years. Boden prints the maximum height for each label:

Boden girls’ and boys’ body measurements
LabelHeightChestWaist
7–8 yearsup to 128 cmup to 64 cmup to 58 cm
8–9 yearsup to 134 cmup to 67 cmup to 60 cm
9–10 yearsup to 140 cmup to 70 cmup to 62 cm

John Lewis uses single-age labels. Its "8 years" size is cut for the height a child reaches at 8, which is the same as Boden's "7–8". That is why one shop's 8 feels small next to another's 8–9.

John Lewis boyswear and girlswear guides
John Lewis sizeHeightChest (boys / girls)Waist (boys / girls)
8 years128 cm64 / 59 cm65 / 58 cm
9 years134 cm67.5 / 61 cm68 / 60 cm

If they're between sizes, go by height first, then chest for tops and waist for bottoms. More on this in kids’ clothes sizes by height.

Shoes

Two UK shoe shops publish an "average size by age". They don't quite agree, so you get a range:

AgeShoe Zone averageMarshmallow Kids chart
8 yearsUK 1–2UK 12.5–13

Feet vary more than height does, so measure heel to longest toe in centimetres and use the kids’ shoe size chart by foot length. Buying a European brand? Use the EU to UK shoe size converter.

Bike

Most 8 year olds ride a 20". Trek starts 24" at 130 cm and lists it for 9–11 years, so only a tall 8 year old needs one.

WheelRider height (Raleigh)Inside leg (Raleigh)Approx. age (Trek)
20"114–129 cm53–63 cm6–8 years
24"128–143 cm57–68 cm9–11 years

Cycling UK's rule of thumb: the wheel diameter in inches should be no bigger than the child's inside leg in inches. Full tables in the kids’ bike size chart.

Scooter

A larger "maxi" style scooter or a two-wheeler. Micro designs its Maxi for ages 5–12. Whatever the brand, the handlebar should sit somewhere between belly button and mid-chest. See scooter size by age.

Bike helmet

Halfords' guide puts 8 year olds in its Juniors size (7+ years), 52–59 cm. Helmets are sized by head circumference, not age, so measure about two finger-widths above the eyebrows. Fit checks are in the helmet size guide.

Bed and duvet

Dunelm suggests 4.5–9 tog for children over three, depending on the season: about 7.5 tog in winter and 2.5–4 tog in summer. A single bed takes a 135 × 200 cm duvet.

More detail in what tog duvet for a child. Pyjamas follow the same age labels as clothes: see kids’ pyjama sizes.

School uniform

Uniform is often sold in inches. Your School Uniform's chart puts the 7/8 yrs age band at:

Item7/8 yrs
Sweatshirts, cardigans, polo shirts, PE T-shirts, blouses (chest)28"
Knitwear (chest)30"
Boys’ blazers (chest)28"
Girls’ blazers (ladies’ size)6
Boys’ shirts (collar)12½
Trousers and skirts (waist)24"
Boys’ school shorts (waist)24½"
Jog bottoms (waist)22"

Full chart and how to measure: school uniform sizes explained.

Questions

What clothes size does an 8 year old wear?

Usually 8–9 years. Boden cuts that label for children up to 134 cm tall. If they are taller, go up a size.

What shoe size is an 8 year old?

Shoe Zone and Marshmallow Kids put the average at around UK 12.5 to 2, but foot length varies a lot, so measure in centimetres.

What size bike for an 8 year old?

Most 8 year olds ride a 20". Trek starts 24" at 130 cm and lists it for 9–11 years, so only a tall 8 year old needs one.

Where these numbers come from

Checked 18 October 2026. Brands change their charts, so always check the size guide of the shop you're buying from.