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Understanding 38DD Bra Size

A 38DD bra size is considered a medium band size with an extra full cup size. This size is perfect for people with an average frame and extra full breast volume. Let's explore what makes this size unique and how to find the perfect fit.

Is 38DD considered big or small?

Fast facts about 38DD

  • Snug 38 band with a 5-inch cup jump.
  • Standing bust around 42.5–43.5 in keeps the cup filled.
  • Share cup volume with 36E, 40D for band tweaks.
  • Always scoop-and-swoop and check the gore for a flat anchor.

How 38DD is measured

Band fit

Aim for a snug 36.5–37.5 in underbust so the 38 band stays level without digging.

Cup depth

Standing bust in the 42.5–43.5 in range keeps roughly a 5-inch cup difference.

Support focus

Choose firm wings, fully adjustable straps, and swap sister sizes if the band shifts during wear.

38DD bust size in inches

MeasurementTypical inchesHow to capture it
Snug band (ribcage)36.5–37.5 inMeasure firmly under the bust on an exhale, then round to the band label.
Standing bust42.5–43.5 inKeep the tape level across the fullest point while standing tall.
Band-to-bust difference≈5 inSubtract your snug band from the standing bust to confirm cup depth.
Approx. cup depth6.5–7.5 inMeasure from the underwire root to the apex on a well-fitting bra.

38DD bust size in centimeters

MeasurementTypical cmHow to capture it
Snug band (ribcage)92.7–95.3 cmMeasure firmly beneath the bust, then map it to EU/FR/JP band labels.
Standing bust108–110.5 cmKeep the tape level across the fullest point without compressing tissue.
Band-to-bust difference≈12.7 cmUse the difference to double-check your metric cup depth.
Approx. cup depth16.5–19.1 cmTrace from underbust to apex on a supportive bra to check projection.
  • Falls inside the 32-36 band range most people wear, giving a familiar fit baseline.
  • Carries more volume than a standard D cup, so it can look prominent on petite bands.
  • Monitor posture and band tension—small shifts change how the size looks.
  • Try sister sizes 36E, 40D to fine-tune band tension.

Quick reference for 38DD

  • 38DD ≈ band 38 label with a 5-inch cup step.
  • Projected bust lands around 42.5–43.5 in.
  • Use the calculator to convert this size across US/UK/EU/JP systems.

Ranges are approximations—double-check your own measurements for precision.

38DD across popular sizing systems

Match US 38DD to the most searched regional labels without leaving this guide.

Currently showing the United States (US) label — copy 38DD to match tags instantly.

  • United States (US)

    38DD

  • United Kingdom (UK)

    38DD

  • Europe (EU)

    85E

  • France (FR)

    100E

  • Japan (JP)

    90E

  • Australia (AU)

    16DD

Quick converter

Switch systems and copy the exact label for checkout forms or bra tags.

Need step-by-step help? Jump into the dedicated guides below for measurement nuances and shopping tips.

Perfect For

  • Average frames
  • Medium ribcages
  • Extra full breast volume
  • Premium support needs

Recommended Styles

T-Shirt Bras

Perfect for everyday wear under fitted clothing

  • Seamless
  • Molded cups
  • Comfortable

Balconette Bras

Great for creating a natural lift and shape

  • Wide-set straps
  • Lower cut cups
  • Enhancing

Plunge Bras

Ideal for low-cut tops and dresses

  • Deep V-neck
  • Minimal coverage
  • Versatile

How 38DD tends to look

38DD pairs a 38-band with a 5-inch cup jump, so the silhouette changes with your frame and bra style.

  • Keep 36E, 40D in mind—they share cup volume while tweaking the band.
  • Shape, strap placement, and fabric choice all influence whether the size looks subtle or bold.

38DD compared with nearby sizes

Quick reference when you’re deciding whether to change the band, the cup, or both.

  • 38D is one cup shallower—switch when 38DD wrinkles along the neckline.
  • 38E adds depth while keeping the band snug if you spill out of 38DD.
  • 36E / 40D keep the same cup volume but tweak band tightness for comfort.

Sister size playbook

  • Try 36E when you need tighter or looser band support.
  • Try 40D when you need tighter or looser band support.

Fit checks before you buy

When trying on 38DD bras, look for these key fit indicators:

  • The band should fit snugly around your ribcage
  • Cups should fully contain your breasts without spillage
  • Straps should stay in place without digging in
  • The center gore should lie flat against your chest

  • Keep the band parallel to the floor on the middle hook.
  • Scoop and swoop tissue into the cups before checking the gore.
  • Adjust straps for lift, then reassess comfort after an hour of wear.

Remember that fit can vary between brands and styles. Always try on bras before purchasing to ensure the perfect fit.

Common 38DD questions

What size is 38DD in other systems?

38DD converts to 38DD in UK sizes, 85E in EU, 100E in FR, 90E in JP, and 16DD in AU.

What does 38DD mean?

38DD pairs a 38 band with a cup that is roughly 5 inches deeper than the band measurement.

Which sister sizes match 38DD?

38DD shares cup volume with 36E, 40D. Use them to tighten or relax the band.

How can I confirm this is my best fit?

Measure snug and standing bust, check for smooth cup edges, and ensure the band stays level after a few minutes of wear.

Check 38DD with our tools

Measure with the calculator, compare sister sizes, and review the perception guide for styling tips.