Fit guide · Inclusive
For AMAB bodies. Same fire.
Perfect Blue is about two selves, both loud — so nobody sizes out of ours. This guide shows how to measure and choose lingerie for an assigned-male-at-birth frame, converted straight to our UK sizing. No guesswork, no gatekeeping.
Take four measurements
Grab a soft tape and work in front of a mirror. Snug, level, honest. Note each number in centimetres or inches — the chart below takes both.
Chest / bust
Around the fullest part of your chest, tape level and snug, arms down. This is the number most bralette and bodysuit tops are cut to.
Underbust / band
Directly under the chest, where a bra band sits. Keep it firm and level — it sets the band size on anything with structure.
Waist
The narrowest part of your torso, usually an inch above the navel. Don't suck in — measure the real you.
Hips / seat
The fullest part of your hips and seat, feet together. This drives the fit of briefs, teddies and anything one-piece.
Your size in Perfect Blue
Measurements in cm (inches). Land between two sizes? Size up.
| Size | UK | Chest | Waist | Hips |
|---|---|---|---|---|
| S | UK 8 | 80–86 (31–34) | 62–70 (24–27) | 86–93 (34–37) |
| M | UK 10–12 | 87–95 (34–37) | 71–79 (28–31) | 94–101 (37–40) |
| L | UK 14 | 96–103 (38–40) | 80–88 (31–35) | 102–109 (40–43) |
| XL | UK 16–18 | 104–112 (41–44) | 89–98 (35–39) | 110–118 (43–46) |
A guide, not a rule — cuts vary by style. Every product page lists its own measured fit where it differs.
Fit notes worth knowing
Size to your biggest number
Pick the size that fits your largest relevant measurement — often the chest, waist or shoulders — then let the stretch do the rest. Between two sizes? Go up.
Mind the torso
Bodysuits, teddies and one-pieces are cut for an average torso length. If you're long through the body, size up one for length so straps and gussets sit right rather than pull.
Shoulders & straps
Broader shoulders love adjustable and strappy styles — most of ours adjust. Halter and multi-strap cuts carry a fuller upper frame beautifully.
Tucking is optional
If you tuck, measure your hips and seat while tucked for the truest brief and bodysuit fit. If you don't, size for comfort — high-cut and cheeky cuts are the most forgiving.
Now go get noticed loudly.
Still unsure between two sizes? Message us before you order — we'd rather get it right than have you send it back.
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