Theory Size Charts
Complete sizing guide for Theory with measurements, fit tips, and global conversions
Theory offers sizing across men, women. Use the tabs to filter by category, or scroll to see all available charts with measurements and conversions.
Fit Summary
Theory offers modern, minimalist professional wear with a slim, tailored fit. Their clothing runs true to size with a polished, body-conscious cut. Known for excellent stretch fabrics in workwear.
Last updated: Q3 2026 · Reviewed quarterly by JC, SizeHub editor
Men's Sizing
Tops & Shirts
| Size | US | Chest (in) | Waist (in) | Neck (in) |
|---|---|---|---|---|
| XS | 34 | 34-36 | 28-30 | 14-14.5 |
| S | 36 | 36-38 | 30-32 | 14.5-15 |
| M | 38-40 | 38-40 | 32-34 | 15-15.5 |
| L | 42-44 | 42-44 | 34-36 | 15.5-16 |
| XL | 46-48 | 46-48 | 36-38 | 16-16.5 |
| XXL | 50-52 | 50-52 | 38-40 | 16.5-17 |
Pants & Bottoms
| Size | Waist (in) | Hip (in) | Inseam (in) |
|---|---|---|---|
| 28 | 28 | 34 | 30-32 |
| 30 | 30 | 36 | 30-32 |
| 32 | 32 | 38 | 30-32 |
| 34 | 34 | 40 | 30-32 |
| 36 | 36 | 42 | 30-32 |
| 38 | 38 | 44 | 30-32 |
Women's Sizing
Tops & Shirts
| Size | US | Bust (in) | Waist (in) | Hip (in) |
|---|---|---|---|---|
| XS | 0-2 | 31-32 | 24-25 | 34-35 |
| S | 4-6 | 33-34 | 26-27 | 36-37 |
| M | 8-10 | 35-36 | 28-29 | 38-39 |
| L | 12-14 | 37-39 | 30-32 | 40-42 |
| XL | 16-18 | 40-42 | 33-35 | 43-45 |
Pants & Bottoms
| Size | US | Waist (in) | Hip (in) | Inseam (in) |
|---|---|---|---|---|
| 24 | 00 | 24 | 34 | 28-30 |
| 25 | 0 | 25 | 35 | 28-30 |
| 26 | 2 | 26 | 36 | 28-30 |
| 27 | 4 | 27 | 37 | 28-30 |
| 28 | 6 | 28 | 38 | 28-30 |
| 29 | 8 | 29 | 39 | 28-30 |
| 30 | 10 | 30 | 40 | 28-30 |
| 31 | 12 | 31 | 41 | 28-30 |
| 32 | 14 | 32 | 42 | 28-30 |
Shopping Tips
True to size for most people. Their Good Wool and Treeca lines are bestsellers. If between sizes, stay true — the stretch fabrics are forgiving.
Size Comparison
Similar to Hugo Boss in tailoring. Slimmer than Brooks Brothers. More professional than Vince.
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Frequently Asked Questions
Does Theory run true to size?
Yes, very consistently. Their stretch fabrics accommodate slight variations.
Is Theory good for work clothes?
Excellent — they specialize in elevated professional wear with comfort stretch.
What are Theory's best sellers?
The Treeca pant and Good Wool blazer are perennial favorites.
How to Measure
Chest
Measure around the fullest part of your chest, keeping the tape horizontal.
Waist
Measure around your natural waistline, keeping the tape comfortably loose.
Hips
Stand with feet together and measure around the fullest part of your hips.