Pants Size Calculator: Waist + Inseam in One Step
By Mohit Patel, Marketing Specialist, Tailor Size Guide
This pants size calculator combines waist, hip, and inseam in one form so you don't have to size chinos, trousers, formal pants, and joggers across three different tools. Enter your numbers, pick your cut (slim, regular, relaxed), and get sizes in US, UK, EU, and JP — including the inseam length recommendation for your height. Use the calculator below to get your exact fit in 30 seconds.
How it works
Measure yourself
Take your bust, waist, and hips with a soft tape. See the full measurement guide.
Enter the numbers
Type your measurements into the calculator above. Pick inches or cm — the tool converts both ways.
Get your size
Match the result against the brand's chart and order with confidence.
Women's waist sizes: the body waist each W size is cut for, with US, UK and EU sizes
| Body Waist | W-Size | US Numerical | UK | EU |
|---|---|---|---|---|
| 27¼" (69 cm) | W26 | 2 | 10 | 38 |
| 29¼" (74 cm) | W28 | 6 | 12 | 40 |
| 31¼" (79 cm) | W30 | 10 | 14 | 42 |
| 34¼" (87 cm) | W32 | 14 | 16 | 44 |
| 37¾" (96 cm) | W34 | 18 | 18 to 20 | 46 to 48 |
| about 39½" (100 cm) | W36 | — | 20 to 22 | 48 to 50 |
Frequently Asked Questions
What's the difference between pants and trouser sizing?
None functionally — both use waist + inseam. 'Trousers' is the British/formal term, 'pants' is American/casual. Same chart applies.
How do I pick my inseam length?
Stand barefoot and measure from the crotch to the floor in inches. For dress pants worn with shoes, add 1 inch. For ankle-cropped, subtract 2.
Should I size up for chinos vs jeans at the same waist?
Match exactly. Chinos and jeans use the same W (waist) numbering. Some chino brands run 0.5 large because the fabric is less rigid.
How accurate is this for joggers and athletic pants?
Joggers run roomy by design. Match the calculator number for a true fit, or size down 1 for a tapered look.
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