Step #1

How to find your waist measurement

Every great pair of underwear starts with accurate measurements. Here’s how to find your best fit with our elastic-free undies:

  1. What You Wear Matters! Start in light clothing or your underwear to avoid adding bulk around your waist area.
  2. Measure Your Waist: Stand up straight and relax your abdomen. Wrap a soft measuring tape around your natural waist, which is typically the narrowest part of your torso. Find this spot by bending to one side—the crease that forms is your natural waist.
  3. Check your Measuring Tape Position: Make sure the tape is snug but not tight, straight and level around your body. Breathe normally and check the measurement after exhaling to ensure it’s comfortable and accurate.
  4. Record the Number: This measurement, in inches, is your waist size. Jot it down so you can refer to the size chart after step #2.

Step #2

How to find your low hip measurement

  1. Find the Right Spot: Start by identifying the fullest part of your hips. This is usually located around the area where your buttocks are most prominent. Stand with your feet together to ensure an accurate measurement.
  2. Measure Your Low Hip: Take a soft measuring tape and wrap it around your low hip area.
  3. Check Your Measuring Tape Position: Ensure the tape is horizontal and snug, but not tight, across the widest part of your hips. The tape should sit level on your skin without creating indentations.
  4. Record the Measurement: While standing straight and relaxed, read the measurement on the tape. This is your low hip size, write it down and use it in reference to the chart below.

At iteration, we recognize the importance of a perfect fit. Our garments are designed to accommodate a range of body shapes and comfort levels, making them exceptionally versatile. To find your size in our products, take your waist + low hip measurements, and consult the size chart, and select the size that best aligns with your measurements.

underwear size chart in inches

Need to know how to measure your underwear size? Click Here!

Between sizes? Go for the larger option for a comfier fit, go smaller for a firmer + more snug fit.
ITERATION SIZE US DRESS SIZE WAIST (INCHES) HIPS (INCHES)
XS 0 - 4 24" - 26" 34" - 37"
S 4 - 6 26" - 28" 37" - 39"
M 8 - 10 28" - 31" 39" - 41"
L 12 - 14 31" - 34" 41" - 44"
XL 16 - 18 34" - 37" 44" - 47"
1X 18 - 20 37" - 41" 47" - 51"
2X 20 - 22 41" - 45" 51" - 55"
3X 22 - 24 45" - 49" 55" - 60"
NOTE: Our fabric is really stretchy and two sizes might work for some people. If you prefer a firmer fit, we suggest selecting the smaller size. If you prefer a comfier fit, we suggest selecting the larger size.
If you're selecting a low-rise or mid-rise style, we recommend you base your size mostly on your hip measurement.
If you're selecting the high rise style, pick the size where the measurement range falls closest to both of your measurements.

Don't see your size here? We continue to add sizes based on community feedback. Let us know what size you need by joining the community.


Whether you're dressing for a special occasion, heading to work, or enjoying a lazy day at home, our style guide is designed to help you select the perfect pair of panties. Consider your outfit, desired level of comfort, and personal style when choosing among our silhouettes. Remember, the right pair of panties can boost your confidence and ensure you look and feel your best, no matter the occasion.

Explore our collection and find your perfect fit today. Welcome to comfort, style, and confidence with iteration underwear.

Below is your go-to resource for selecting the perfect pair of panties for any outfit, day, or mood.

built to last iteration underwear

Low-Rise Bikini

Casual and versatile, the Low-Rise Bikini offers a playful, laid-back look with moderate coverage, making it an everyday essential.

  • Rise // Low-Rise; sits comfortably on the low hips.
  • Waistband // Soft, stretchable fabric that conforms to your body for the perfect fit with a slight v-front to flatter your shape.
  • Coverage // Moderate back coverage with a low-rise waistband that sits comfortably on the hips.
  • Legline // Elastic-free; cut to sit naturally on the leg, ensuring no riding up or discomfort.
  • Why Choose This // Your best bet for everyday wear, especially under low-rise jeans or shorts. It's the ultimate blend of comfort and casual style for any outing or relaxed day.

Mid-Rise Hipster

A modern classic, the Mid-Rise Hipster combines comfort with coverage, offering a contemporary cut that hugs your body just right.

  • Rise // Mid-Rise; offers a natural fit around the middle, just below the waist.
  • Waistband // Wide, fabric-covered waistband that evenly distributes pressure for all-day comfort.
  • Coverage // Generous back coverage with a mid-rise waistband that offers a flattering fit without digging into your sides.
  • Legline // Elastic-free; softly hugs without cutting in, providing ease of movement.
  • Why Choose This // When you want a mix of comfort and coverage that's just right. It's the ideal choice for wearing under almost any outfit, providing a secure fit without compromising on style or comfort.

Mid-Rise Thong

Sleek and minimal, our Mid-Rise Thong offers a no-show profile, perfect for wearing under form-fitting dresses and pants.

  • Rise // Mid-Rise; sits just below your natural waist.
  • Waistband // Elastic-free edges for a smooth, invisible look under clothes.
  • Coverage // Minimal back coverage with a comfortable mid-rise waistband that sits smoothly against your skin.
  • Legline // Elastic-free; seamless transition from waist to leg opening to ensure no visible lines.
  • Why Choose This // Ideal for those days when you want to eliminate panty lines and feel effortlessly sexy. Perfect for tight-fitting outfits or when you're seeking that barely-there feeling.

High-Rise Brief

Our High-Rise Brief provides a classic, sculpted shape with cheeky coverage, designed to offer maximum comfort while flattering your natural curves.

  • Rise // High-Rise; sits at your natural waist.
  • Waistband // Supportive double-layer fabric waistband to grip without digging in.
  • Coverage // Moderate coverage; designed to be cheekier with somewhat more visible bum.
  • Legline // Elastic-free; high-cut French cut leg line; hip bones may be exposed.
  • Why Choose This // A go-to for days when you crave extra support or wish to create a smooth silhouette under high-waisted skirts and pants. It's also the perfect comfort choice for lounging at home.