Global Fit Infants-Little kids 0-3months-7yrs Size Guide

This size guide covers Speedo Global Fit infant and little kids' swimwear from 0–3 months through to 7 years. All measurements are body measurements taken from your child's body, not garment measurements. For girls, always use the chest measurement as the primary guide, supported by height. For boys, use the waist and hip measurements as the primary guide. International size equivalents (D, F, I, Lat Am, Aus, USA, CAN, MEX) are included in the sizing table below.

Shop Boys' Toddler Swimwear → Shop Girls' Toddler Swimwear →
How to Measure

Take all measurements directly against your child's skin using a soft tape measure. All measurements are body measurements, not garment measurements.

  • A
    HeightMeasure your child's full standing height from the top of the head to the floor. Use as a secondary guide alongside chest.
  • B
    ChestMeasure around the fullest part of the chest, keeping the tape horizontal and snug but not tight. This is the primary sizing measurement.
  • C
    WaistMeasure around the waist 5cm below the natural waist at the narrowest point.
  • D
    HipMeasure around the widest part of the hips, 10cm below the natural waist.

*Waist is measured 5cm below the natural waist at the narrowest point. **Hips are measured 10cm below the natural waist around the widest point.

Sizing Table — Speedo Global Fit Infants & Little Kids (0–3 Months to 7 Years)
Sizing 0–3 months 3–6 months 6–9 months 9–12 months 2yrs 3yrs 4yrs 5yrs 6yrs 7yrs
International Size Equivalents
GB Age 0–3 months 3–6 months 6–9 months 9–12 months 2yrs 3yrs 4yrs 5yrs 6yrs 7yrs
D (Germany) — Height 50–62cm 62–68cm 74–80cm 80–86cm 92cm 98cm 104cm 110cm 116cm 122cm
F (France) 0–3 mois 3–6 mois 6–9 mois 9–12 mois 2 ans 3 ans 4 ans 5 ans 6 ans 7 ans
I (Italy) 0–3 mesi 3–6 mesi 6–9 mesi 9–12 mesi 2 anni 3 anni 4 anni 5 anni 6 anni 7 anni
Lat Am Talla 0–3 meses Talla 3–6 meses Talla 6–9 meses Talla 9–12 meses Talla 2 Talla 3 Talla 4 Talla 5 Talla 6 Talla 7
Aus 0–3 months 3–6 months 6–9 months 9–12 months 2 3 4 5 6 7
USA 0–3 months 3–6 months 6–9 months 9–12 months 2yrs 3yrs 4yrs 5yrs 6yrs 7yrs
CAN 0–3 months 3–6 months 6–9 months 9–12 months 2yrs 3yrs 4yrs 5yrs 6yrs 7yrs
MEX 0–3 months 3–6 months 6–9 months 9–12 months 2yrs 3yrs 4yrs 5yrs 6yrs 7yrs
Body Measurements (cm)
Height 56 62 68 74 92 98 104 110 116 122
Chest 43 46 47 48 52 55 56 58 61 62
Waist* 42 44 46 47 51 52 53 55 56 58
Hip** 41 44 47 48 53 56 58 61 64 66

*Waist is measured 5cm below the natural waist at the narrowest point. **Hips are measured 10cm below the natural waist around the widest point. All measurements are body measurements, not garment measurements. Height is shown as a guide only.

Fit Notes — Speedo Global Fit Infants & Little Kids
  • For girls, always use the chest measurement as the primary guide when selecting a size. Use height as a supporting reference, particularly for the youngest sizes.
  • For boys, use the waist and hip measurements as the primary guide. Both should fall within the same size — if they suggest different sizes, use the hip measurement to decide.
  • Age is shown as a guide only — babies and young children grow at different rates, so always measure and compare to the size table rather than selecting by age alone.
  • For girls, if chest and hip measurements suggest different sizes, choose the size that fits the chest. The chest is the hardest area to adjust in a one-piece swimsuit.
  • Speedo infant swimsuits are designed to fit closely and securely — they feel firmer than a regular fitted top to ensure the suit stays in place in the water.
  • Speedo swimwear is made from chlorine-resistant fabrics that ease slightly with wear — do not size up based on initial tightness.
  • Rinse in cold fresh water immediately after every use. Do not tumble dry, iron, or dry-clean.
  • Unsure? Contact our team or call +44 1827 330600.
Frequently Asked Questions — Speedo Infant & Little Kids' Swimwear

Measure your child's chest, height, waist, and hips against their skin with a soft tape measure. For girls, use the chest as the primary guide with height as a supporting reference. For boys, use the waist and hip measurements as the primary guide. Age is shown as a guide only — always use body measurements to confirm the right size.

We recommend sizing to your child's current measurements rather than sizing up for growth. Swimwear that is too large will not stay in place in the water and may be unsafe for young swimmers. Speedo's chlorine-resistant fabrics ease slightly with wear, so a correctly fitted suit will remain comfortable over time.

For girls, use the chest measurement to decide — if the chest falls between two sizes, choose the larger size. For boys, use the hip measurement to decide. For very young children, height can also help confirm the right size. Speak to a member of staff at Allens if you are unsure.

Yes. Speedo infant and toddler swimwear is designed for regular pool use and made from chlorine-resistant fabric suited to frequent swimming lessons. A well-fitted suit that stays securely in place is particularly important for young children in the water.

Speedo infant swimwear sizes do not directly correspond to standard babywear or clothing sizes. Always use body measurements to select the correct size. The age equivalents shown in the table are a secondary guide only — babies develop at different rates and the same age can correspond to significantly different body measurements.

Most public pools require babies and toddlers who are not yet toilet trained to wear a swim nappy under their swimsuit. Speedo offer a range of reusable swim nappies designed to be worn under their infant swimwear. If you need guidance on sizing swim nappies alongside a swimsuit, speak to a member of staff at Allens.

Rinse in cold fresh water immediately after every use to remove chlorine, salt, and sunscreen. Hand wash gently with a mild detergent if needed. Do not machine wash, tumble dry, iron, or dry-clean. Store flat and dry, away from direct sunlight.