Infant Shoe Sizes US: Complete Size Chart with cm Measurements

US infant shoe sizes cover babies from approximately 0 to 18 months, with foot lengths ranging from 7 cm (US size 0, newborn) to 13 cm (US size 7, approximately 18 months). US infant size 3 fits a foot length of approximately 9.5–10 cm (Indian/UK size 2, EU 18–19, age 6–9 months). US infant size 6 fits a foot length of approximately 12–12.5 cm (Indian/UK size 5, EU 22, age 15–18 months). EU infant size 23 fits a foot length of approximately 14–14.5 cm, corresponding to US size 8C and Indian/UK size 8 (age 2–2.5 years — technically toddler, not infant).

TABLE OF CONTENTS

1. What are US infant shoe sizes?
2. Complete US infant shoe size chart with cm measurements
3. Infant shoe size 1 and 2 — newborn sizing
4. Infant shoe size 3 and 3C
5. Infant shoe size 3.5
6. Infant shoe size 4 and size 3 infant shoes
7. Infant shoe size 5
8. Infant shoe size 6
9. Infant shoe size 7 — the 7 infant shoe size explained
10. What is infant shoe size 23 (EU)?
11. Printable infant shoe size guide — how to measure at home
12. US infant to Indian/UK conversion
13. When to move from infant to toddler shoe sizing
14. Frequently asked questions

INTRODUCTION

Baby shoe shopping should be simple. It is not.

Walk into any store or open any website selling infant shoes and you will encounter at least three different ways of labelling the same size: a US number (3, 4, 5), a C-size (3C, 4C, 5C), an EU number (19, 20, 21), and possibly an Indian/UK number (2, 3, 4). These are all different systems describing the same foot length — but because no global standard exists, each brand picks whichever system it prefers, and parents are left converting between them every time they shop.

Add to this the fact that babies grow out of shoes every 6–8 weeks in the first year, and the stakes of getting the size wrong are real: a shoe that is too small can restrict foot development; one that is too large causes the foot to slide and creates blisters.

This guide gives you the complete US infant shoe size chart — every size from 0 to 7 — with foot length in centimetres, Indian/UK equivalents, EU sizes, the age each size fits, and a step-by-step method for measuring your baby's foot at home without a special tool.

What Are US Infant Shoe Sizes?

US infant shoe sizes are a numeric scale used by American shoe brands and many international brands to size footwear for babies from newborn to approximately 18 months. The scale runs from size 0 (newborn, foot length approximately 7 cm) through to size 6 or 7 (approximately 15–18 months, foot length 12–13 cm), after which sizing transitions to the US Toddler or Child (C) system.

Three things to understand about US infant sizing:

1 — US infant sizes and C sizes are the same system used interchangeably
US size 3 and 3C are the same shoe size — the C stands for Child and is simply how some brands (particularly Nike and Adidas) label the same size. A shoe listed as US infant size 3 and a shoe listed as 3C will fit the same foot. For a complete guide to C sizing: What Does C Mean in Shoe Size? 2C, 3C, 5C, 9C, 10C, 11C, 12C Guide

2 — US infant sizes do not appear on Indian or UK shoe labels
Indian and UK baby shoe brands use the Indian/UK numeric system — size 0, 1, 2, 3 and so on. US sizes require conversion. A US infant size 4 corresponds to Indian/UK size 3, not size 4. Never match numbers directly between systems.

3 — EU sizes are a separate scale entirely
EU sizes cannot be derived from US sizes by a simple formula — always convert via foot length in centimetres.

Complete US Infant Shoe Size Chart with cm Measurements

JusCubs US Infant Shoe Size Chart (complete, India reference)

Critical rule: Always add 1–1.5 cm to measured foot length before selecting a size. This growing room is essential — a shoe that fits exactly on the measuring tape will be too small within weeks.

For the complete shoe size reference from newborn through 12 years: Shoe Size & Age Chart for Kids: From Newborn to 12 Years

Infant Shoe Size 1 and 2 — Newborn Sizing

US infant size 1 = foot length 8.0–8.5 cm = Indian/UK size 0–1 = EU 16–17 = age 0–3 months
US infant size 2 = foot length 8.5–9.5 cm = Indian/UK size 1 = EU 17–18 = age 3–6 months

Sizes 1 and 2 are the smallest infant shoe sizes that are widely available in retail. At this age, babies are not walking — these shoes exist primarily for warmth, completing an outfit, or protecting the feet in cold environments.

Important development note: Paediatricians and podiatrists consistently recommend that babies under 12 months who are not walking should not wear rigid-soled shoes. The foot is approximately 80% cartilage at birth — it needs freedom of movement to develop correctly. If you are buying shoes for a baby in sizes 1–2, choose:

• Soft-soled fabric shoes or pre-walkers only
• No rigid heel counter
• No stiff sole — the shoe should be completely foldable
• Socks and booties are equally appropriate at this age

For newborn booties and foot accessories: Newborn Boys — Nappy, Mittens, Booties & Accessories and Newborn Girls — Nappy, Mittens, Booties, Bloomers & Accessories

For newborn clothing at this age: Newborn Boys (0M–12M) and Newborn Girls (0M–12M) — including Body Suits & Rompers, T-Shirts & Jhabla, and Clothing Sets.

For the newborn clothing size reference: Newborn Baby Clothes Size Chart: 0–12 Months

Infant Shoe Size 3 and 3C

US infant size 3 = 3C = foot length 9.5–10.0 cm = Indian/UK size 2 = EU 18–19 = age 6–9 months

Size 3 / 3C is the first shoe size that many parents actively search for — it corresponds to the 6-month milestone when many parents take their baby's first photos in shoes and start thinking more seriously about footwear.

At 6–9 months, most babies are beginning to sit independently, some are crawling, and a small number are pulling themselves to stand. None are walking independently. The same soft-sole guidance applies as for sizes 1 and 2 — rigid soles are not appropriate or necessary at this stage.

Size 3 infant shoes specifically:
The search term "size 3 infant shoes" refers to the same size as US size 3 or 3C. A size 3 infant shoe fits a foot length of 9.5–10 cm. In Indian/UK sizing this is size 2. In EU sizing this is 18–19.

What to buy at size 3:

• Soft fabric pre-walkers — knit, cotton, or suede-upper with no sole rigidity
• Elasticated or velcro opening — easy to put on a baby who pulls their feet away
• No heel counter — the foot needs to flex freely in all directions
• Cotton lining — breathable for India's climate

Infant Shoe Size 3.5

US infant size 3.5 = foot length 10.0–10.5 cm = Indian/UK size 2.5 = EU 19 = age 7–10 months

Size 3.5 is a half size that not all brands carry — many jump from 3 directly to 4. It corresponds to the mid-point of the 6–12-month crawling stage. If your baby's foot measures 10–10.5 cm and you cannot find a size 3.5, choose size 4 — never size down to size 3 when between sizes.

Why half sizes matter at this age: Baby feet at 7–10 months are growing fast — approximately 0.5 cm in foot length per month during growth spurts. A half-size increment (0.5 cm) can make a significant difference in comfort over a 6–8-week wear period. When a brand offers 3.5, it is worth buying rather than skipping to 4 with extra growing room.

Infant Shoe Size 4 and Size 3 Infant Shoes

US infant size 4 = 4C = foot length 10.5–11.0 cm = Indian/UK size 3 = EU 19–20 = age 9–12 months

Size 4 corresponds to the 9–12-month period — when babies are typically pulling to stand, cruising along furniture, and some are taking first independent steps. This is the transitional moment between pre-walker and early walker shoes.

Size 4 is the first size where sole structure begins to matter:

• If your baby is not yet standing: soft sole remains best
• If your baby is pulling to stand or cruising: a thin, slightly structured sole with good grip begins to be appropriate
• If your baby is taking first independent steps: look for a flexible but protective sole — not rigid, but with enough structure to protect the foot from surfaces

Indian/UK equivalent: US size 4 = Indian/UK size 3. When shopping an Indian brand for a baby at this stage, look for Indian size 3 with a foot length of 10.5–11 cm on the product chart.

For clothing at this age — the 9–12-month range: Newborn Boys (0M–12M) for the upper end of the newborn range, and Infant Boys (6M–4Y) and Infant Girls (6M–4Y) for the 6M+ range. For the 1T clothing size guide that corresponds to this age transition: 1T Size in Months: What Age Fits 1T & 1T vs 12–18M Explained

Infant Shoe Size 5

US infant size 5 = 5C = foot length 11.5–12.0 cm = Indian/UK size 4 = EU 20–21 = age 12–15 months

Size 5 is the first walking shoe size for most babies. At 12–15 months, the majority of babies are walking independently — some steadily, others still with the characteristic wide-legged toddler wobble.

First walking shoe criteria at size 5:

• Flexible sole that bends at the ball of the foot — press the toe of the shoe upward and it should give with moderate resistance
• Low cut upper — ankle-height or below; high boots restrict the ankle movement essential for developing balance
• Wide toe box — baby feet are proportionally very wide; a narrow toe box compresses toes and affects the natural toe-off movement during walking
• Lightweight construction — heavy shoes fatigue baby walkers quickly and affect confidence
• Velcro or elasticated fastening — practical for the frequency of on/off at this age
• Thin, grippy sole — carpet, tile, marble, and outdoor surfaces all require different grip; a thin rubber sole handles most surfaces

India-specific note: India's floor surfaces at home — marble, tile, and polished stone — are significantly more slippery than the carpeted floors common in Western countries. For Indian homes, prioritise a sole with a textured rubber grip pattern. Smooth leather soles look beautiful but are genuinely dangerous on polished Indian flooring for a new walker.

For clothing at 12–15 months: Infant Boys (6M–4Y) and Infant Girls (6M–4Y).

Infant Shoe Size 6

US infant size 6 = 6C = foot length 12.0–12.5 cm = Indian/UK size 5 = EU 22 = age 15–18 months

Size 6 is one of the most searched infant shoe sizes — it corresponds to the 15–18-month range when children are walking confidently and becoming increasingly active. Running, climbing on low furniture, going up stairs on hands and knees, and outdoor play all begin in earnest at this stage.

At size 6, the shoe requirements shift slightly from first-walker priorities:

• More durable sole — toddlers at this age are harder on shoes than new walkers
• Better lateral support — side-to-side movement increases significantly as the child becomes more agile
• Easy fastening still important — velcro remains the most practical option; most 15–18-month-olds cannot cooperate with laces at all
• Breathable upper — children at this age generate significantly more heat during active play

Indian/UK equivalent: US size 6 = Indian/UK size 5. For Indian brands, look for size 5 with a foot length of 12–12.5 cm on the product size chart.

How often to replace at size 6: Children at 15–18 months grow approximately 1.5 cm in foot length per year — which is about half a shoe size every 4–5 months. A size 6 shoe bought at 15 months may be outgrown by 19–20 months. Measure monthly and replace when less than 0.5 cm of space remains beyond the longest toe.

Infant Shoe Size 7 — The 7 Infant Shoe Size Explained

US infant size 7 = 7C = foot length 13.0–13.5 cm = Indian/UK size 7 = EU 23–24 = age 18–24 months

Size 7 is the last of the commonly listed infant shoe sizes and overlaps with the start of the toddler range. At 18–24 months, children are running, jumping (attempting to), and beginning activities at playgroups or nursery. The 7 infant shoe size is also sometimes labelled as a toddler size 7 by brands — the underlying foot measurement is identical.

At size 7, look for:

• A more structured sole than early walker shoes — toddlers at this age run on varied outdoor surfaces and need better protection and grip
• Toe bumper or reinforced toe cap — 18–24-month-olds trip and scuff toes constantly during running
• Still velcro — lace tying is years away; buckle is also fine
• Ankle collar with padding — the toddler gait involves significant inward foot roll (pronation), and light ankle support begins to be beneficial

The 7 infant shoe size in Indian sizing: US size 7 / 7C = Indian/UK size 7. This is a coincidence of numbers — do not apply this logic to other sizes. Always verify against foot length: 13–13.5 cm.

For clothing at 18–24 months: Infant Boys (6M–4Y) and Infant Girls (6M–4Y) — including Clothing Sets, T-Shirts & Polo, Trackpants & Joggers, Party Wear. For the corresponding clothing size: What Does 2T Mean? Complete 2T Size Guide for Toddlers

What Is Infant Shoe Size 23 (EU)?

EU size 23 = foot length approximately 14.0–14.5 cm = US size 8C = Indian/UK size 8–8.5 = age 2–2.5 years

EU size 23 is frequently searched as an "infant shoe size" — but technically, EU 23 falls in the toddler range, not the infant range. It fits children aged approximately 2 to 2.5 years with a foot length of 14–14.5 cm. In US sizing this is 8C; in Indian/UK sizing this is 8 or 8.5.

The confusion arises because EU sizing uses a continuous numeric scale with no separate "infant" or "toddler" category label — size 23 sits in the middle of what US and Indian systems would call the toddler range, but EU labelling does not make this distinction.

Full EU size reference for the 18–36 month range:

For the complete EU to Indian/UK to US conversion across all ages: Shoe Size & Age Chart for Kids: From Newborn to 12 Years

Printable Infant Shoe Size Guide — How to Measure at Home

You do not need a special tool to measure your baby's foot accurately. This method works from birth through toddlerhood using items found in any home.

What you need:

• One sheet of A4 paper
• A pencil or pen
• A ruler with centimetre markings

For babies who cannot stand (0–10 months approximately):

Lay your baby on a flat, firm surface on their back. Place the sheet of A4 paper under one foot. Gently press the foot flat against the paper — the heel should be fully in contact with the paper and the toes should be relaxed, not curled. Hold the foot steady with one hand and trace around it with the other, keeping the pencil vertical (not angled inward). Lift the foot and measure from the furthest back point of the heel trace to the tip of the longest toe in centimetres. Repeat for the other foot. Use the larger measurement.

For babies and toddlers who can stand (approximately 10 months and above):

Place the paper on a hard floor. Have your child stand on it with full body weight on both feet. Trace around one foot, keeping the pencil vertical. Measure from heel to longest toe. Use the larger of the two feet.

Calculating the right size:

Find your total (measured length + growing room) in the foot length column of Section 2. Read across to the US size, Indian/UK size, and EU size.

Make this your printable guide: Write your baby's current foot length and shoe size on the back of the tracing. Keep the paper. Retrace every 4–6 weeks — when the new foot trace is noticeably larger than the old one, it is time to measure for the next size.

Remeasure frequency by age:

• 0–6 months: every 4 weeks
• 6–12 months: every 5–6 weeks
• 12–24 months: every 6–8 weeks

US Infant to Indian/UK Conversion

Quick reference — US infant to Indian/UK:

Conversion rule: For most of the infant range (sizes 1–6), subtract 1 from the US size to get the Indian/UK equivalent. Size 7 is an exception where the numbers coincide. As always — verify via foot length, not by relying on the subtraction formula alone.

India-specific shopping note: Most Indian baby shoe brands — Bata Kids, Liberty, Lilliput, and value-range brands on e-commerce platforms — use Indian/UK sizing exclusively. When you see a size on an Indian baby shoe label, use this table to understand the corresponding US size and verify against foot length.

SECTION 13: When to Move from Infant to Toddler Shoe Sizing

The transition from infant shoe sizing to toddler or child (C) sizing happens at approximately US size 7–8 / foot length 13–14 cm / age 18–24 months. At this point, the infant sizing run ends and continues directly as US toddler sizes — the numbering continues without a gap, but the category label changes.

Signs your baby has outgrown infant shoe sizing:

• Foot length measures 13 cm or above with growing room
• Current shoe size is 7 or approaching 7
• Red marks on the top of the toes after wearing shoes
• Toes pressing visibly against the front of the shoe
• Child pulling at the shoes or appearing uncomfortable after short wear periods
• Less than 0.5 cm of space when you press the toe box firmly

What comes next:
US infant size 7 → US toddler size 8 (8C) → continues as 9C, 10C, 11C, 12C, 13C before transitioning to Youth (Y) sizing at approximately age 7.

For the complete C-size toddler guide: What Does C Mean in Shoe Size? 2C, 3C, 5C, 9C, 10C, 11C, 12C Guide

For the preschool shoe size guide: Preschool Shoe Size Chart: What Shoe Size Does a 3–5 Year Old Wear?

For clothing at 18–24 months and beyond: Infant Boys (6M–4Y) and Infant Girls (6M–4Y) — including Clothing Sets, Shorts & Skirts, Frocks & Dresses, Dungarees, Party Wear.

For garment care at this age: How to Wash Newborn & Baby Clothes for the First Time

Headline: Shop clothing for every infant shoe size age at JusCubs
Body: Soft cotton rompers, body suits, T-shirts, clothing sets and accessories for Indian babies from newborn to 4 years. Starting from ₹349.
Button 1: Newborn Boys (0M–12M) → https://www.juscubs.com/collections/newborn-boys-0m-12m-1
Button 2: Newborn Girls (0M–12M) → https://www.juscubs.com/collections/newborn-girls-0m-12m
Button 3: Infant Boys (6M–4Y) → https://www.juscubs.com/collections/infant-boys-6m-4y
Button 4: Infant Girls (6M–4Y) → https://www.juscubs.com/collections/infant-girls-6m-4y

Frequently Asked Questions

What are US infant shoe sizes?
US infant shoe sizes are a numeric scale (0 through 7) used to size baby footwear from newborn to approximately 18–24 months, covering foot lengths from 7 cm (size 0) to 13.5 cm (size 7). They are interchangeable with C sizes — US size 3 and 3C are the same shoe. They require conversion to use with Indian/UK or EU sizing systems.

What is infant shoe size 3 or 3C in Indian sizing?
US infant size 3 (also written 3C) fits a foot length of 9.5–10 cm and corresponds to Indian/UK size 2 and EU size 18–19. It fits babies aged approximately 6 to 9 months. Do not match the number 3 directly to Indian sizing — US 3 and Indian/UK 3 are different sizes.

What is infant shoe size 3.5?
US infant size 3.5 fits a foot length of 10–10.5 cm, corresponding to Indian/UK size 2.5 and EU size 19. It fits babies aged approximately 7 to 10 months. Not all brands carry this half size — if unavailable, choose size 4.

What is infant shoe size 6?
US infant size 6 (6C) fits a foot length of 12–12.5 cm, corresponding to Indian/UK size 5 and EU size 22. It fits children aged approximately 15 to 18 months who are walking confidently. Indian/UK size 5 is the equivalent for shopping Indian brands.

What is 7 infant shoe size in Indian sizing?
US infant size 7 (7C) fits a foot length of 13–13.5 cm and corresponds to Indian/UK size 7 and EU size 23–24. It fits children aged approximately 18 to 24 months. Note: the US and Indian numbers coincide at size 7 — this is an exception, not a rule. Do not apply the same logic to other sizes.

What is infant shoe size 23?
EU size 23 is commonly searched as an "infant shoe size" but technically falls in the toddler range. It fits a foot length of approximately 14–14.5 cm, corresponding to US size 8C and Indian/UK size 8–8.5. It is designed for children aged approximately 2 to 2.5 years.

What is infant size 4 shoes?
Infant size 4 (4C) fits a foot length of 10.5–11 cm, corresponding to Indian/UK size 3 and EU size 19–20. It fits babies aged approximately 9 to 12 months, covering the late crawling and early pulling-to-stand stage.

How do I measure my baby's foot for US infant shoe sizing?
Trace the foot on A4 paper while the baby lies flat (under 10 months) or stands (over 10 months). Measure from heel to longest toe in centimetres. Add 1–1.5 cm for growing room. Match the total to the foot length column in the size chart above. Always choose the larger size when between sizes.

How often should I replace infant shoes?
Under 6 months: every 4 weeks. 6–12 months: every 5–6 weeks. 12–24 months: every 6–8 weeks. Baby feet grow faster than any other period in life — remeasure regularly rather than waiting for visible signs of tightness, since babies rarely communicate shoe discomfort verbally.

What size comes after US infant size 7?
After US infant size 7 comes US toddler size 8 (8C), continuing the Child (C) sizing run: 8C, 9C, 10C, 11C, 12C, 13C. This transitions to Youth (Y) sizing at approximately age 7. For the full toddler C-size guide: What Does C Mean in Shoe Size?

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