Finding your fit
Size Guide
Every body is different. Here's everything you need to find the right size and fit for you.
Step one
How to measure
Two quick ways to find your size before you look at the charts.
Measure your high hip
Wrap a soft tape measure around your hip bones — the area where our low-rise styles sit. This is usually higher than your fullest hip measurement.
Half waist flat lay
Lay your underwear or swim bottoms flat and measure across the top of the waistband, unstretched. This is the most accurate way to match sizing to a garment you already own.
Step two
How each style fits
Same size, different feel. Here's what to expect from each cut.
Super Bikini
Low rise
Most forgiving fit
Brief
Mid rise
More structured feel
Swimwear
Bikinis and one pieces
Firm, secure fit
Swim Shorts
Board short style
Relaxed, comfortable fit
High Waist
High rise
Maximum coverage and support
Racerback
One piece swimsuit
Firmest fit — built for laps
Step three
Find your size
Select your range below and match your measurement to the chart.
Quick note on fit before you look at the charts
Between sizes? Go snug for true to size or size up for a more relaxed fit. There's no wrong answer. Most customers find that sizing up feels more comfortable for everyday wear.
Teen sizing is based on body measurements, not age. Find the high hip measurement that matches and that's your size.
| Girls Size | High Hip (cm) |
|---|---|
| 8–10 | 60–66 cm |
| 10–12 | 66–72 cm |
| 12–14 | 72–78 cm |
| 14–16 | 78–86 cm |
| 16–18 | 86–94 cm |
If your child is between sizes or prefers a more relaxed fit, sizing up is often more comfortable.
Measure around your high hip — the area over your hip bones where our low-rise styles sit. Sizing is based on this measurement, not the fullest part of the hip.
| AU Size | High Hip (cm) | Half Waist Flat Lay (cm) ① |
|---|---|---|
| 6 | 75–80 cm | 30 cm |
| 8 | 80–86 cm | 32 cm |
| 10 | 86–92 cm | 34 cm |
| 12 | 92–98 cm | 36 cm |
| 14 | 98–104 cm | 38 cm |
| 16 | 104–110 cm | 40 cm |
| 18 | 110–116 cm | 42 cm |
| 20 | 116–122 cm | 44 cm |
| 22 | 122–130 cm | 46 cm |
| 24 | 130–138 cm | 48 cm |
① Half waist flat lay: Lay your underwear flat and measure straight across the waistband, unstretched. A size 12 measures 34 cm flat, which equals approximately 68 cm around your body.
Important: These measurements are based on the high hip (hip bones), not the fullest part of the hips. If you're curvier through the hips or prefer a more relaxed fit, we recommend sizing up.
Period swimwear is sized to fit snugly in the water. Measure your high hip and match it to the chart. If you prefer a more relaxed swim fit, size up.
| AU Size | High Hip (cm) | Half Waist Flat Lay (cm) |
|---|---|---|
| 6 | 75–80 cm | 31 cm |
| 8 | 80–85 cm | 33 cm |
| 10 | 85–90 cm | 35 cm |
| 12 | 90–95 cm | 37 cm |
| 14 | 95–100 cm | 39 cm |
| 16 | 100–105 cm | 41 cm |
| 18 | 105–110 cm | 43 cm |
| 20 | 110–115 cm | 45 cm |
Swimwear fits more firmly than underwear and is designed to stay secure in the water. These measurements are based on the high hip. If you are between sizes or prefer a more relaxed fit, we recommend sizing up.
Every body is different — and so is every style.
Things that can affect fit: rise (low, mid, high waist), fabric type (cotton vs swim), personal comfort preference (firm vs relaxed).
Still not sure? We're here to help.
Chat with us or send an email and we'll help you find the right size. No question is too small.
Email us at info@ecoperiod.com.au