Coffee bag sizes, degassing valves and zippers, explained

Three formats, one coffee

The stand-up pouch (doypack) stands on its bottom gusset, shows a wide front and works well on shelves and in online-store photos. The side-gusset bag is the classic roaster format: narrow front, plenty of room on the sides and efficient use of shipping cases. The flat-bottom (block bottom) bag combines a firm base with five printable faces and is common at 500 g and 1 kg. All three formats take a valve and a zipper; the choice depends on your sales channel and how you display the coffee.

Reference dimensions by size

Manufacturers publish indicative dimensions per gram range. Packstyle recommends, for coffee, bags of 11 × 19 + 7 cm, 13 × 22 + 7 cm, 15 × 25 + 7 cm, 19 × 26 + 11 cm and 24 × 31 + 10 cm depending on the gram range, with the advice not to fill a bag beyond two thirds. Hyperbolsas, in Mexico, suggests 11 × 21 cm with a 7 cm base for about 100 g of roasted beans and 27.5 × 31 cm with a 10 cm base for about 2 kg. These are references: real capacity depends on roast density, whole bean or ground, the gusset and how much air is left when sealing.

• Whole beans take more volume than ground coffee for the same weight; ask for the size with your product, not a generic figure.
• Dimensions are written as width × height + gusset; the printable front area is smaller than width × height because of the seals.
• Fill five samples with your coffee, seal them and check that they stand and that the valve sits where the artwork expects it.

How a degassing valve works

After roasting, coffee releases carbon dioxide for days. If the bag is sealed with no outlet, it swells. A one-way valve opens when internal pressure reaches a certain level and lets the gas escape; at the same time it closes to keep oxygen out. That is why, according to the manufacturer Plitek, coffee can be packed immediately after roasting. There are clear valves that do not interfere with the artwork, metallised valves, filtered valves for ground coffee and mini versions for small bags.

• Decide the valve position (front, back or side) before closing the design: the zone must stay free of mandatory text.
• If your coffee rests for several days before packing, discuss with production whether the valve is still needed in your process.
• For ground coffee ask for a filtered valve so powder does not block the membrane.

Zipper, tin-tie or just a notch

A zipper lets the customer reclose the bag and is the usual option on stand-up and flat-bottom bags. The tin-tie, the foldable wire of traditional bags, is used mostly on side-gusset bags. If the coffee is consumed within days or the bag is a sample, a tear notch is enough. A zipper adds material and a horizontal strip the artwork must respect; the notch should sit above it so the customer opens the bag without damaging the closure.

Material, window and artwork per origin

Coffee is sensitive to oxygen, moisture and light, so typical structures carry a metallised or aluminium barrier between the printed layer (PET, kraft paper or matte film) and the sealing layer. A clear window shows the beans but lowers the barrier. The finish (matte, gloss, kraft, metallic) is a brand decision; the exact structure is confirmed by production against your product brief. With digital printing, origin, farm, process or roast date can change per design within one order if the bag is the same.

• Reserve space on the dieline for the mandatory information of the country where you sell.
• Use an artwork system: what is fixed (logo, format, legal zone) and what varies (origin, color, tasting notes).
• State how many bags you want of each origin; sharing production depends on matching size, structure and closure.

What to test before approval

Before approving artwork and production, fill samples of the proposed format with your coffee and check: that the filled bag stands, that the top seal closes well with beans inside, that the valve does not sit over text, that the zipper opens and closes several times and that the bag survives a drop from table height. A printed proof of the artwork on the real material shows how color looks on kraft or metallised film, which is not the same as on screen.