A customer-facing size chart and a factory garment specification are related, but they do different jobs. The size chart helps a shopper choose a size. The garment measurement sheet tells the pattern and production teams what the finished product should measure. When a buyer sends only body measurements, a competitor’s chart, or a list of Small–XL labels, the factory still has to guess the intended fit.
This guide explains how to separate body, garment and grading information so a custom apparel supplier can evaluate the style, prepare a pattern and measure samples against a clear reference.
Start with the intended fit, not the size label
A size name is not a universal dimension. Medium may describe a close-fitting active top, a regular unisex T-shirt or an oversized sweatshirt. Before building a measurement table, define the wearer, silhouette, layering need and intended use. Reference images can help, but label each image with the feature it demonstrates: body length, shoulder shape, sleeve volume or overall ease.
Choose one base size for development. This is the size used to review the initial pattern and sample before the range is graded. The base size should represent the core customer rather than simply copying the middle column of an unrelated chart.
Understand the three measurement layers
Body measurements
Body measurements describe the person the garment is designed to fit. They are useful for defining the target customer and building a consumer size guide. They do not, by themselves, specify the finished garment because the pattern must add or remove ease according to the silhouette and fabric behavior.
Finished garment measurements
Finished garment measurements describe the product when measured using agreed points of measure. Examples include half chest, body length, shoulder width, sleeve length and bottom opening. These values belong in the technical specification and should be reviewed against the physical sample.
Grade rules
Grade rules describe how each measurement changes between sizes. The change does not need to be identical at every point, and it may vary across the size range. A sleeve opening, shoulder and body length can each require a different increment. Confirming these rules is more useful than asking the supplier to “grade proportionally.”
Define every point of measure
A number is only reproducible when the measurement method is clear. Give each point a code, name, diagram location and written method. State whether the garment is measured flat, whether openings are relaxed or extended, where the tape begins and ends, and whether curves are followed or measured straight.
| Specification field | What to record | Why it matters |
|---|---|---|
| Point code | A stable identifier such as POM 01 | Keeps comments aligned across files |
| Measurement name | Clear product-specific wording | Avoids ambiguous shorthand |
| Method | Start, end and garment position | Makes the result repeatable |
| Base-size value | Target finished measurement | Guides pattern and sample review |
| Tolerance | Permitted production variation | Supports a practical inspection decision |
| Grade rule | Change between adjacent sizes | Defines the full size range |
Use a diagram whenever two people could interpret a point differently. For example, front body length might be taken from the high point shoulder, from the side neck or from the center front. A marked drawing removes that uncertainty before sampling begins.
Set tolerances by product and measurement
Tolerance is not a second target measurement. It is the agreed variation allowed around the target when finished garments are checked. Avoid applying one tolerance to every point. A small neck opening, a long body dimension and an elasticated waistband behave differently in cutting, sewing and finishing.
Ask the manufacturer to review whether each tolerance is practical for the fabric, construction and finishing route. Stretch, wash treatments, quilting and bulky seams can affect measurement stability. If a point is especially important to fit or function, identify it as critical and discuss how it will be controlled rather than silently tightening the number.
Build the grading plan before approving the range
Start with the approved base size, then review how the garment should change for smaller and larger wearers. Look at proportion as well as circumference. A wider body may also need changes to shoulder position, armhole depth, sleeve width and length. The correct relationship depends on the style and target customer.
- List the complete size range and identify the base size.
- Show the grade increment for every point of measure.
- Flag split grading where increments change in extended sizes.
- Confirm whether labels, packaging and order files use the same size names.
- Decide which additional sizes need physical fit review.
For complex sizing, request a graded nest, measurement table or additional sample sizes as appropriate to the project. The goal is to approve the range logic, not to assume that a good base sample automatically creates a good full size run.
Check samples against one controlled file
Keep one current specification with a clear revision date. When a sample arrives, measure it using the same methods shown in that file. Record the actual result, the difference from target and the decision. Do not overwrite the target with the sample measurement or combine comments from several versions.
Fit comments should explain the observed problem and the intended result. “Add 2 cm to half chest” is a specification change; “increase mobility through the upper body without changing the hem width” is a fit objective that may require a broader pattern review. Separating objectives from proposed corrections helps the pattern team evaluate connected measurements.
Use the same disciplined review alongside an apparel tech pack for sampling. Before bulk production, work through the sample approval checklist and define the relevant garment quality-control points.
Common specification problems to resolve early
- Body and garment measurements are mixed: label each table and explain the intended ease.
- Reference samples conflict: state which feature is taken from each reference.
- Measurement methods are missing: add diagrams and written instructions.
- Only the base size is supplied: provide grade rules before approving the full range.
- Tolerances are copied across every point: review them according to construction and function.
- Revisions are spread across messages: consolidate approved changes into one controlled file.
What to send with your first sizing brief
A useful first package includes the product category, wearer, intended fit, base size, target size range, body-size reference, finished garment measurements, measurement diagrams and any available physical reference. Mark information that is fixed and information that remains open to supplier recommendation.
If you are developing a new style, browse the custom apparel product range for a relevant starting point, review the available OEM and ODM development routes, then share your project brief with the product type, quantity, reference images, material direction, sizing information and required delivery window.