How this instrument works
US Misses dress sizing (00 through 20) is nominally anchored to ASTM D5585-21, 'Standard Tables of Body Measurements for Adult Female Misses Figure Type,' the currently active formal standard published by ASTM International for translating body measurements into apparel pattern sizes. This calculator compares your entered bust circumference against a reference table of bust values, one per size, and returns whichever labeled size sits closest to your measurement.
Read that description carefully, because it comes with a real caveat: ASTM's own exact published numeric breakpoints weren't directly available to build this table from, so the twelve reference bust values used here are a disclosed, deliberately conservative approximation assembled from commonly published ASTM-aligned sewing-pattern bust charts — not a verbatim transcription of the ASTM standard itself. Treat the result as a reasonable body-measurement estimate in the spirit of the standard, not a certified reproduction of it.
The much bigger caveat, though, is this: real-world retail garment sizing varies substantially by brand and frequently doesn't match ASTM's body-measurement tables at all. A size 10 on this calculator's ASTM-aligned scale might show up on a store rack as anywhere from a size 6 to a size 14 depending on the brand — a well-documented pattern often called 'vanity sizing,' where labeled sizes have drifted larger over the decades relative to actual body measurements. Use this tool to estimate your ASTM body-measurement size, then treat any specific retailer's own size chart as the final word for that brand's clothes.
- Measure your bust circumference in inches, wrapping the tape around the fullest part of your bust, level across your back.
- Keep the tape snug but not compressing, and take the reading in a well-fitted (not padded) bra.
- Enter that figure into Bust circumference (inches).
- Read Nearest Misses size — the ASTM-aligned reference size closest to your measurement.
- Read Reference bust for that size to see exactly how close (or far) your measurement sits from the size's reference point.
- Cross-check against the specific brand's own size chart before buying — this figure is a body-measurement estimate, not a brand-specific fit guarantee.
Worked example — a 40-inch bust measurement
A 40-inch bust circumference is compared against the reference table's nearby entries: size 14 sits at a reference bust of 39.5 in (0.5 in away), while size 16 sits at 41.0 in (1.0 in away). Size 14 is closer, so that's the result returned, alongside the 39.5 in reference figure so you can see exactly how the match was made.
For comparison, a bust of exactly 36.5 in lands precisely on the size-10 reference point with zero difference — the cleanest possible match. And a bust of 45 in, above the top of this table's 12-point range (the largest reference is size 20 at 44.0 in), still resolves to size 20 rather than extrapolating a size the table doesn't cover — worth knowing if your measurement sits well above or below the table's 30.5-44.0 in span.
Questions
Will my calculated size match the tag on clothes I buy?
Often not, and that's genuinely expected rather than a flaw in the calculator. Real-world retail sizing varies substantially by brand — a phenomenon often called vanity sizing, where labeled sizes have drifted larger over the decades relative to actual body measurements — so a size 10 on this ASTM-aligned scale might land anywhere from a size 6 to a size 14 depending on which store you're shopping at. Use this figure as a body-measurement starting point, then check the specific retailer's own size chart before ordering.
What is ASTM D5585-21, and is it the standard my clothes are actually sized to?
ASTM D5585-21 is a currently active standard published by ASTM International that tabulates body measurements for adult female Misses figure types, sizes 00 through 20 — it's meant to give apparel manufacturers a consistent starting reference. In practice, most retail brands don't strictly follow it; many use their own in-house sizing developed from their specific customer base and fit preferences, which is the core reason store sizes and body-measurement standards diverge so much.
Why does this calculator only use bust measurement, not waist and hip too?
The full ASTM D5585-21 standard is actually a combined bust, waist, and hip body-measurement table, not a single-measurement lookup — this calculator simplifies to bust alone since it's the single most commonly available and quickly measured figure. If your waist-to-bust or hip-to-bust ratio differs noticeably from an average Misses figure, your best-fitting size for a specific garment (especially a fitted dress) may differ from what bust alone suggests, particularly for tops versus bottoms.
How should I measure my bust for the most accurate result?
Wear a well-fitted, non-padded bra, and wrap a soft tape measure around the fullest part of your bust, keeping the tape level and parallel to the floor all the way around your back. Keep the tape snug against your body without pulling it tight or letting it sag, and take the reading while breathing normally rather than holding your breath.
My measurement is below 30.5 in or above 44 in — what does the result mean?
The reference table used here spans size 00 (30.5 in) through size 20 (44.0 in), and it doesn't extrapolate beyond those endpoints — a bust measurement outside that range still returns the nearest table endpoint (00 or 20) rather than a size below or above it. If your measurement falls well outside this span, you're likely looking at a petite, plus, or tall-specific size range that this general Misses-scale calculator doesn't cover; check a size chart specific to that category instead.