Trotters Size Guide: How to Measure & Fit for Baby and Children's Clothing

January 28, 2026

Finding the perfect fit for your child can often feel like a moving target. One moment they are snug in their newborn sleepsuits, and the next, they’ve had a growth spurt that seems to have happened overnight. At Trotters, we understand that "size" is about more than just a label on a collar—it is about ensuring your child feels comfortable, confident, and ready to make memories, whether they are attending a winter wedding or heading off for their first day of school.

"A Trotters outfit is designed to be part of a memory, whether it's a first birthday or a first day at school. We cut our garments with traditional British elegance in mind, meaning a neat, tailored fit. Measuring by height, rather than just age, ensures your little one is as comfortable as they are stylish." – Trotters Team.

The "Golden Rule" of Children's Fitting: Height Over Age

When navigating a baby clothes size chart UK parents often start with age, but this can be misleading.

Why Age is Just a Number

Growth rates vary wildly between children. In their first year alone, babies typically grow approximately 25cm in length and triple their birth weight. Because every child develops at their own pace, a "6-month-old" label might fit one baby perfectly while being far too small for another.

The Trotters Fit: Traditional vs. High-Street

At Trotters, our heritage lies in a "Traditional/Heritage" cut. This means our clothing is often more tailored and smarter than the baggy, oversized fits frequently found on the high street. Our girls' dresses and boys' trousers are designed for a neat, classic silhouette that honours British tailoring.

How to Measure Your Child (Step-by-Step)

To get an accurate reading, it is best to measure your child in their underwear or a light vest.

Measuring Babies (0-24 Months)

Measuring a wriggling baby requires patience!

Length: Lay your baby on a flat surface and measure from the crown of the head to the heel. It helps to have a second person hold their legs gently straight.
Chest: Wrap the tape measure around the fullest part of the chest, just under the arms.

Measuring Children (2 Years +)

Height: Have your child stand barefoot with their back flat against a wall. Measure from the top of the head to the floor.
Chest & Waist: The tape should be snug but not tight. For the waist, measure the natural waistline just above the hip bone.
Hips & Inside Leg: Crucial for boys' trousers and party wear, measure from the crotch to the desired length at the ankle.

Finding the Right Size

To make things easy, we have created comprehensive data charts to help you choose the best fit based on your measurements.

Baby Size Guide: 0 to 24 Months

Choosing between "Newborn," "Up to 1 Month," and "0-3m" can be confusing for new parents. If your baby is nearing the top end of the height or weight range for a size, we always recommend moving up to the next bracket to allow for growth and comfort.

For a full breakdown of heights, weights, and chest measurements for little ones, please visit our Baby Clothes Size Guide.

Children's Size Guide: 2 Years to 12 Years+

As children grow, height becomes the most reliable indicator for a perfect fit in our girls' knitwear and boys' coats.

Between sizes? If your child falls between age brackets, we advise rounding up. A slightly longer sleeve on a tailored coat can be rolled up, often allowing the garment to last two seasons.

For detailed height, chest, and waist measurements for older children, please see our Children's Clothing Size Guide.

The "Gift Givers" Cheat Sheet

Did you know that 1 in 3 gift returns are due to sizing issues? If you are buying a gift and cannot measure the child, the safest bet is to buy one size up from their current age. This ensures the child will eventually grow into the piece, especially if you are choosing from our Shop All Baby Girls' or Shop All Baby Boys' ranges.

Accessories & Hat Sizing

Measuring Head Circumference

Crucial for our sun hats and winter beanies, measure around the widest part of the head, just above the ears. A hat that is too tight can be uncomfortable, while one too large may slip over their eyes during play.

Sock & Tights Sizing

Socks and tights are generally linked to shoe size. For children's tights, if they are particularly long in the leg, choosing the next size up prevents the gusset from "dropping" during the day.

Garment Care & Shrinkage

Because we use premium natural fibres like cotton and wool, please allow for very slight shrinkage after the first wash. Following the care labels meticulously will help maintain the tailored fit of your Trotters pieces for years to come.

Frequently Asked Questions

Does Trotters run true to size? Yes, but our traditional cuts are more tailored. If your child is tall or you prefer a roomier fit, size up.
My baby is chubby but short, which size do I pick? Prioritise chest and waist measurements over height to ensure they are comfortable and not restricted.
How do I measure for a Christening gown? Occasion wear requires a neat fit. Focus on the chest measurement and ensure there is enough room for a nappy without pulling the fabric.

Unsure about the measurements? Our customer service team are ready to help! Contact us for personal fitting advice, or visit us in-store to see the full range first-hand.