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Fit & Sizing

Standard Size vs. Custom Size Dresses

Start with your measurements, not your usual dress size. A standard size follows a chart; custom sizing uses the measurements you submit for the selected style. The useful choice is the one you can support with accurate numbers and clear answers about fit, timing, and terms.

Last updated: September 28, 2026PromSpark Editorial Team
Lavender floral A-line tulle prom gown photographed outdoors
Compare current measurements to the size guide before selecting standard or custom sizing.

Read a standard size as a set of measurements

PromSpark's formal-gown chart lists body measurements, not the measurements of a finished dress laid flat. Compare bust, natural waist, hips, and hollow to floor in the same unit. A familiar size number from another brand does not tell you how these measurements line up.

For example, the published US 6 row lists a 35-inch bust, 28.5-inch waist, and 38.5-inch hips. US 8 lists 36, 29.5, and 39.5 inches respectively. If your bust is 35 inches but your waist is 29.5 inches, those two measurements land on different rows. That is a reason to ask a fit question, not a reason to average the size labels or round your waist down.

A chart also does not establish which options are offered on every product. Open the size selector on the dress you want. If your measurements or a needed option are not covered, contact support instead of assuming that a listed chart size can be ordered for that style.

Know what Custom can and cannot resolve

Where a product offers Custom, it provides a way to submit your measurements for that style. It does not by itself confirm a different neckline, extra coverage, a new fabric, or any other design change. Ask about a requested change separately and get a clear answer before ordering.

Custom sizing still depends on the numbers you provide. It does not guarantee that a finished dress will need no local adjustments. A photo cannot settle questions about stretch, lining, or how the bodice will support you; ask about the exact dress rather than inferring those details from its silhouette.

If a standard size appears close, do not choose Custom just because it sounds like the more complete option. If your measurements span rows, do not assume the largest row is automatically correct either. Send your full set of measurements and the product link so support can address the combination.

Check the numbers before choosing either path

Use a flexible tape and avoid bulky clothing. Following the size guide, measure around the fullest bust with the tape level across your back; measure the natural waist without holding your breath; then stand with your feet together to measure the fullest hips. Ask someone to help if you cannot keep the tape level.

Measure hollow to floor from the hollow between your collarbones down to the floor. Record the heel height you plan to wear with a long gown separately, and follow the product's instructions for how to submit it. Do not quietly add shoe height to one field if the form asks for it in another.

Label every number with inches or centimeters and the date measured. Repeat a measurement if it changes noticeably between attempts. If you are planning in the fall but ordering later, remeasure at ordering time instead of relying on an old note or a size you hope to wear. Keep a copy of the numbers you actually submit.

Compare the terms as carefully as the fit

Custom-size dresses are not eligible for change-of-mind returns. The Terms preserve applicable legal rights and remedies for damaged, defective, wrong, or materially misdescribed items. Read Shipping & Returns before choosing Custom; do not treat it as a way to order several sizes for a home comparison.

A standard-size dress not marked final sale can be requested for a change-of-mind return within 14 calendar days after delivery if it meets the condition requirements. You pay return shipping, a 15% restocking fee is deducted from the dress refund, and the original shipping charge is not refunded. These change-of-mind fees do not apply to issues we are responsible for. Read the steps before ordering and ask support if a specific item is marked final sale.

Finish your fit question with the event date and destination: 'My measurements are [numbers and units], taken on [date]. For [dress link and color], should I consider a standard size or Custom, and what should I confirm about the length and timing?' Plan a first try-on with your shoes and leave room for any adjustments you decide on after seeing the dress.

Questions, answered

Frequently asked questions

Is custom size the same as a fully altered dress?

No. Custom size uses the measurements you provide as the starting point. It does not guarantee that no local alterations will be needed.

Should I size up if my measurements fall on different rows?

Do not choose from one measurement alone or average the size labels. Send your complete measurements, units, and dress link to support for guidance on that style.

Does Custom include design changes?

Do not assume it does. Custom sizing uses submitted measurements; ask separately about any neckline, coverage, fabric, or other design change.

Can I return a custom-size dress?

Not for a change of mind. Contact support promptly if the dress is damaged, defective, wrong, or materially not as described; applicable legal rights remain. Read Shipping & Returns for the steps.

Should I use measurements saved earlier in the school year?

Take current measurements before ordering, label the units, and record the date. Earlier measurements can help you learn the chart but should not replace a fresh check.

Your next step

Keep the decision clear.

Use the details that matter for your event, then explore the styles and fit information at your own pace.

View the Size Guide