"Do I need a tech pack" and "what goes in one" are asked constantly in the apparel startup subs, and the replies are a mix of genuinely useful and quietly commercial, because tech-pack tools and freelance designers both fish for leads in those threads. Fair warning on who is writing this: I co-own a vertically integrated garment manufacturer, so I read tech packs for a living and I have a commercial interest in you sourcing carefully. So this page does the work in the open. I pulled the real threads from r/streetwearstartup through public archives, quoted them verbatim with links, kept the parts where the crowd argues, flagged the answers that are really ads, and then added what a tech pack looks like from the factory side of the table.
What is a tech pack, and do you actually need one?
A tech pack is the technical spec a factory uses to build your garment, and on reddit the honest consensus is you almost always need one, with a narrow exception for very simple pieces. The most upvoted answer to a first-timer asking whether factories will just figure it out put the tradeoff plainly:
"sometimes if its simple you can go without but depending on the manufacturer it might be a good idea to buy a tech pack on etsy or something so you avoid a lot of revisions down the line."
That is the real function of a tech pack in one sentence: it is not paperwork, it is the thing that removes revisions. Every detail you specify up front is a detail nobody has to guess at during sampling or bulk. The founder who asked the question, in a 2026 r/streetwearstartup thread, "Do factories usually help with adjusting the patterns?", is in the exact spot most first brands start: a visual idea, a sketch, and no idea how to turn it into something a factory can cut. The answer is that some factories will help and some will build precisely what you send and nothing more, which is the next question.
What has to be in a tech pack for a factory to build it right?
A workable tech pack carries measurements, fabric, trims, stitching, and label placement, and reddit's experienced posters recite that list almost the same way every time. In a r/streetwearstartup thread, "How to create tech pack if you have the design already," one poster gave the cleanest checklist in the sub:
"as long as you have all measurements, fabrics for both shell and lining, stitching type and trimmings (size, position, color), then most samples will turn out alright."
Notice the framing: "most samples will turn out alright." Nobody credible promises a perfect first sample, because a sample round exists precisely to catch what the flat drawing could not show. The same poster made the practical point that the flat sketch just has to be legible: proportional, big enough that details read on an A4 print, with tricky details zoomed onto a separate page. A tech pack is not art. It is a set of instructions clear enough that two different people on a line would build the same garment.
What happens when the tech pack is vague?
You pay to rework the batch. The most useful thread on the whole topic is a manufacturer-side post titled "We had to rework 120 units because of one missing line in the tech pack," and it is worth reading in full because it is the exact failure mode I see most:
"When the bulk came in, the collars felt a bit inconsistent... we hadn't clearly defined the collar construction in the tech pack. It was left a bit open. Factory handled it in two slightly different ways depending on who was on the line. We ended up reworking part of the batch just to bring it back to one standard."
The poster's own conclusion is the sentence every founder should tape above their desk: "If something isn't clearly defined, it doesn't stay open. It just gets decided during production." That is the whole argument for a tech pack. Sampling went fine, fabric was locked, fit was approved, and a single unspecified line, collar construction, still cost a rework across 120 units, because an underspecified detail does not wait for you. Two operators made two reasonable choices and the batch came back inconsistent. The tech pack is where you spend the decision so the line does not have to.
Are AI tech pack tools good enough yet?
Not for the final document, and reddit's technical designers are blunt about why. When a brand owner shared an AI-generated tech pack in a 2026 r/streetwearstartup thread asking whether his designer was wrong to want it rebuilt from scratch, the top reply named the actual limitation:
"AI doesn't give editable vector outputs. You cannot easily edit jpegs, tech packs are made in vector. Editing a jpeg in photoshop for simple lines is ridiculous."
That is the real seam. AI tools are getting genuinely useful for a first draft, the flats, the layout, a starting measurement chart, but a tech pack lives and dies on editable vector flats and a graded measurement spec that a technical designer and a factory can revise cleanly across sample rounds. A raster export you cannot edit becomes a liability the first time a measurement changes. The pragmatic reply in that same thread is the one I would give: "Just send it to the factory and see what they say" (u/CorrectWheels). A factory's sample room will tell you within one round whether your tech pack, AI-made or not, is buildable. Treat the tool as a head start, not the deliverable.
How many of reddit's tech pack answers are actually ads?
A lot of them, and the crowd polices it in real time. Almost every tech-pack thread has a reply naming a low price or a slick tool, followed by a link to that same tool. The "do factories help" thread has a "100% recommend" pitch for a named tech-pack app; the "how to create" thread has the same app's account replying to upload your artwork, plus a fashion student offering "flat technicals front and back" for 15 dollars. In the AI thread, one commenter cut straight to it: "This is a shitty advertisement" (u/makwabear), and another questioned why you would use a designer who insists you route the tech pack through their own tool. None of that means the tools are useless. It means the reddit signal is noisy, and the rounder and cheaper the pitch, the more likely there is a link attached and a lead being fished. The honest replies tend to be the ones that hand you a checklist and tell you the first sample still has to prove it.
The routes to a tech pack, side by side
| Route | What the threads say | Factory-owner read |
|---|---|---|
| Bought template (Etsy, marketplace) | "buy a tech pack on etsy or something so you avoid a lot of revisions" (r/streetwearstartup) | Fine for a simple, standard garment. Falls short the moment your piece has non-standard construction the template never anticipated |
| Freelance technical designer | Common once volume grows; "$15 for flats front and back" up to full paid engagements | The reliable middle. You get editable vector flats and a real measurement spec, which is what survives revisions |
| AI tech-pack tool | "AI doesn't give editable vector outputs... tech packs are made in vector" (r/streetwearstartup) | A fast first draft, not the final file. Great for the flat and layout, weak on editable vector and graded measurements |
| Factory develops from your sketch | "did you find a manufacturer that helped you develop the patterns from scratch?" (r/streetwearstartup) | Real, but "help" ranges from full pattern development to none. A cut-make-trim shop builds exactly what you send; a full-package maker can pattern from a sketch, but then you are trusting their interpretation |
| Vertically integrated maker | Not in the threads. The crowd only sees template vs freelancer vs tool | One owner controls pattern, fabric spec, and the line, so an underspecified detail gets flagged in the sample room instead of surfacing as a reworked bulk order |
What does a factory owner add?
The threads treat a tech pack as a document. On the factory floor it is a contract about who eats the ambiguity, and that reframe changes three things.
The tech pack transfers decisions from the line back to you. This is the whole lesson of the 120-unit rework. Every field you fill in is a decision you make once, on paper, instead of one an operator makes differently on Tuesday than on Wednesday. A "vague" tech pack is not incomplete paperwork, it is a stack of decisions you handed to whoever happens to be on the line. That is why "it depends on the manufacturer" is a real answer, not a dodge: a careful factory catches the gap and asks; a cheap one just builds it two ways and ships.
The sample round is where the tech pack is proven, not the bulk order. No first tech pack is perfect, and it does not need to be. It needs to be clear enough that the sample exposes the gaps while a fix is still cheap. The failure in the rework thread was not a bad tech pack, it was an open detail that survived into bulk because sampling did not force the question. Build your tech pack so the sample round has to make every ambiguous line explicit, then lock it before you cut 120 of anything.
"Do factories help?" depends on what kind of factory. A pure cut-make-trim shop builds precisely what you send and is not responsible for what you left out. A full-package or vertically integrated maker can develop the pattern from your sketch, but then the interpretation is theirs, so you still want to review and approve the flats and the graded spec they produce. Either way, the fabric side hides its own tech-pack trap: specify the shell and lining fully, because a fabric substituted to hit a mill minimum can quietly change the hand, the stretch, and the shrinkage your fit sample was approved on. That fabric-minimum mechanic is the subject of our small-batch roundup. If your category is one of ours, the technical detail lives on the cornerstone pages: activewear, intimates, basics, lingerie, and swim. The wider sourcing sequence is in how to find a clothing manufacturer, per reddit, and the budget side in how much it costs to start a clothing brand, per reddit.
So what should your first tech pack actually contain?
Build it in the order the line reads it. First, a clean, proportional flat sketch, front and back, in editable vector, big enough that details survive an A4 print. Second, a full measurement spec with a size run, not a single sample size. Third, the fabric for shell and lining named to a real quality, with weight and content, plus every trim by size, position, and color. Fourth, the construction and stitch callouts, especially anything non-standard like a collar, cuff, or seam finish, because those are the lines that "get decided during production" if you leave them open. Fifth, labels and their exact placement. Then send it to a factory sample room and let one sample round tell you what the drawing could not. Do that and you skip the rework, which is the entire point of a tech pack. If fabric is the part you are least sure of, the plastic-free activewear pillar has the full technical case, methods included.
Sources
Every thread cited on this page, so you can read the originals: r/streetwearstartup · "We had to rework 120 units because of one missing line in the tech pack" · r/streetwearstartup · "Designing my first piece but have zero tech pack experience. Do factories usually help with adjusting the patterns?" · r/streetwearstartup · "How to create tech pack if you have the design already" · r/streetwearstartup · "My tech designer says this tech pack should be rebuilt from scratch". Quotes are verbatim from public comments and posts, lightly truncated with typography normalized, attributed to their reddit usernames. Threads were read via public archives at the time of writing and may have changed.