Tech Pack vs. Spec Sheet: What’s the Difference?
Factories, freelance pattern makers, and online guides all use “tech pack” and “spec sheet” as if they mean the same thing. They overlap, but they are not identical, and mixing them up can leave a factory with an incomplete file when you thought you had sent everything they needed.
The Short Answer
A spec sheet, short for specification sheet, is a single document focused on measurements: a flat sketch with a point of measure chart and tolerances for each size. A tech pack is a larger file that includes the spec sheet along with the bill of materials, construction notes, colorways, and labeling instructions.
In other words, every tech pack contains a spec sheet, but a spec sheet on its own is not a complete tech pack.
What a Spec Sheet Covers
A spec sheet typically includes a flat sketch, a list of measurement points, the target measurement at each point per size, and a tolerance range for acceptable variation. Some factories use the term to mean exactly this and nothing more, which is why it is worth confirming with any new supplier what they expect when they ask for one.
What a Tech Pack Adds
A full tech pack builds on the spec sheet with several additional sections:
- A bill of materials listing every fabric and trim, with supplier and consumption details
- Construction notes on seam types and stitching
- Colorways with exact Pantone or color codes per component
- Labeling and packaging placement
- A revision history tracking every change sent to the factory
This is the difference that matters most once you move from a single sample to full production, since a factory quoting only from a spec sheet has to guess at materials and construction, and guesses tend to show up as unwanted surprises in the finished sample.
Which One Do You Actually Need?
A spec sheet alone can work for very early fit testing with a sample maker you already trust, where materials and construction are being figured out together in person. For anything sent to a factory sight unseen, especially overseas manufacturing, a full tech pack removes far more room for error.
Rather than building both separately, most brands start from a single tech pack template that includes the spec sheet as one of its sections. That way, the measurement details never end up out of sync with the materials and construction notes sent alongside them.
If your measurements are still evolving, keep your grading rules up to date in both the spec sheet section and the size chart you show customers, so the two never drift apart after a revision.
Frequently Asked Questions about Tech Packs and Spec Sheets
No. A spec sheet is the measurement-focused portion of a tech pack. A full tech pack includes the spec sheet plus the bill of materials, construction notes, colorways, and labeling instructions.
Some can for early sampling with a trusted maker, but most factories, especially overseas ones, need the full tech pack to quote and produce accurately without guessing at materials or construction.
No. Some factories use “spec sheet” loosely to mean any technical document, including a full tech pack. Always confirm exactly what a new supplier expects before sending your file.
No, it is simpler to use one tech pack template that includes the spec sheet as one of its sections, so measurements always stay consistent with the rest of the file.
