Mailing Bag Size Guide
Measure the packed item, distinguish the bag body from the closure flap, and confirm usable space before you request a quotation.
- W — Bag width
- L — Bag body length
- F — Closure flap length
- Usable space
Space between seals after allowing for the closure; confirm internal dimensions with a sample.
1. Measure the item as it will ship
Fold or assemble the product exactly as it will be packed. Include inner wrapping, protective material and any inserts. Record the length, width, thickness and weight. An empty bag measured flat does not show how much internal space remains after a bulky item is inserted.
2. Separate body length and flap length
State usable body width × body length, plus the separate closure flap length. Supply mm or inches (1 inch = 25.4 mm). Identify internal or external dimensions and check fit with a sample.
3. Check the bag construction
For a flat bag, confirm the usable opening and space between seals. For a bottom-gusset bag, state both the flat dimensions and the fully opened base dimensions on a drawing. For mailing bags on a roll, also identify the bag pitch, perforations and opening orientation. Do not compare supplier dimensions until you know which measurement convention each uses.
4. Test fit and sealing with a sample
Insert the packed item without forcing the seams. Check that the closure reaches its intended sealing area and that a shipping label can be applied without hiding the opening. Evaluate the package in the actual packing workflow. There is no universal extra allowance suitable for every product: confirm the final size using a sample or an agreed drawing.