Why the spec sheet decides the outcome
A buyer sends a reference photo and a sentence such as "high waist, squat-proof, soft". The factory fills the gaps with its own defaults, the first sample comes back with a different waistband, a different fabric and no gusset, and the next three weeks go into correcting assumptions. None of that is a quality problem. It is a documentation problem.
A leggings spec sheet is the short, structured part of a tech pack that answers every question a pattern maker, a fabric buyer and an inspector will ask. It does not need to be long. It needs to be complete, numbered and versioned, so that comments on sample one and sample two refer to the same fields. If you are building the full tech pack, our tech pack guide covers the drawings and measurement pages; this note focuses on the fields themselves.
The field list, grouped by who uses it
| Group | Fields | Used by |
|---|---|---|
| Style basics | Style number, season, version date, size range, target customer and practice | Everyone; the anchor for all comments |
| Route | Cut and sew or seamless knit | Desk and factory assignment |
| Fabric | Composition, base and finished GSM with tolerance, structure, finish, colors | Fabric buyer and mill |
| Construction | Waistband build, seam types, gusset, pockets, hem finish | Pattern maker and sewing line |
| Measurements | Points of measure, base size values, tolerances, grade rules | Pattern maker and inspector |
| Trims and branding | Logo method and placement, labels, thread, elastic | Trims buyer and finishing |
| Testing | Opacity check, stretch and recovery, pilling, colorfastness, dimensional change | Quality team and lab |
| Packing | Fold, polybag, size sticker, hang tag, carton marks | Packing line and logistics |
Style basics and route
The first block looks administrative, but it prevents most mix-ups. A style number with a version date tells everyone which sheet is current. The size range tells the pattern maker how many sizes to grade and tells the desk how the MOQ will be split. The target practice, for example heated flow or reformer pilates, explains why a field is set the way it is, which helps the factory flag conflicts early.
State the route explicitly. Cut and sew leggings are usually made in a cluster such as Humen, Dongguan, where gussets, pockets and color blocking are routine. Seamless leggings are knitted as a tube on electronic circular seamless knitting machines, more often in the Yiwu cluster, and are specified by knit program rather than by fabric roll. The route also shapes the typical reference MOQ: around 100-300 pcs per style per color for cut and sew, around 300-500 for seamless, confirmed in writing for each program. See seamless vs cut and sew if the route is still open.
Fabric fields
Write the composition as the mill states it, for example a nylon and spandex interlock in the 75-80% nylon and 20-25% spandex range. Give base and finished GSM, because brushing can add 5-15 GSM, and note the tolerance, typically about plus or minus 5% of nominal. Name the lightest color in the line, because opacity is approved on that color. Fabric details are covered in depth in the leggings fabric guide.
Construction fields
This block is where reference photos are least reliable. Write each construction choice as a field with one answer:
- Waistband: height as set on the tech pack, number of layers, whether elastic is inserted, and whether there is a hidden pocket.
- Seams: flatlock or coverstitch, and where each is used.
- Gusset: none, diamond or triangle, and the fabric for it.
- Pockets: none, hidden waistband pocket or side drop-in pockets, with opening direction.
- Hem: coverstitched, bonded or laser-cut edge.
Each of these choices changes the pattern, the sewing time and the inspection checklist, so leaving one blank means the factory decides it for you.
Measurement fields
List points of measure with a short description of how each is taken: waist relaxed, waist extended, front rise, back rise, hip, thigh, knee, leg opening and inseam. Give values for the base size only at first, plus a tolerance per point. Common length options such as a 25 in 7/8 inseam or a 28 in full length are a starting point, not a standard; the value you choose is set on the tech pack and size chart. Grade rules come after the base sample fits. Our size chart and grading note explains that sequence.
Trims and branding fields
Name the logo method (heat transfer, silicone, reflective print or embroidery on woven pieces), its size and its position measured from a fixed seam. List the woven or printed neck or waistband label, the care label with fiber content and country of origin, and the hang tag. For US sales, fiber content, origin and dealer identity on the label follow the Textile Fiber Products Identification Act, and care instructions follow the Care Labeling Rule, so these fields should be filled from your compliance notes rather than copied from a reference garment.
Testing fields
A testing block turns "good quality" into checks that can pass or fail. Typical lines for leggings include a documented squat or opacity review on the lightest color, which is a practical sample method rather than an official standard; stretch and growth to ASTM D2594; pilling to ASTM D4970 or ISO 12945-2; colorfastness to laundering, such as AATCC 61, and to perspiration, such as AATCC 15 or ISO 105-E04; and dimensional change after laundering to AATCC 135. Write which checks are on fabric and which are on the finished garment, and who pays for third-party testing if you need it.
Packing fields
Packing is often left until bulk and then improvised. Specify the fold, the polybag type and any warning text, the size sticker, whether the hang tag is attached or packed loose, units per carton and carton marks. These fields are cheap to fill early and slow to fix after cartons are sealed.
Versioning and sign-off
Every comment round should produce a new version date and a short change list at the top of the sheet. When the sample is approved, the sheet version is recorded with the approval and becomes the inspection reference for bulk. That single habit makes reorders far smoother, because the second run is checked against the same fields as the first.
If you have a reference style and a partial sheet, the desk can mark the open fields before sampling starts. Start with the leggings overview or send your sheet for review.