Dimensions / Industrial & logistics / Poly mailers / Bubble mailer
Poly bubble mailers are numbered #000 to #7. A #0 is 6 × 10 in outside at Uline and Sealed Air but 6.5 × 10 in at IPG, and its usable space is 5 7/8 × 8 3/4 in at Uline, 6.25 × 9 in at IPG and 6 × 9 in at JiaroPack: the number is a convention, not a standard. Size the item against the usable size, which is 1 to 1 1/4 in shorter than the outside. Uline lines its mailers with 3/16 in bubble inside 2.4 mil film; European makers use letter codes with inside sizes in millimetres, from 120 × 215 mm for VP’s 2/B to 350 × 470 mm for its 10/K.
| #0 bubble mailer, outside W × L (Uline, Sealed Air) | #0 usable size (Uline) | Bubble lining; outer film (Uline) |
|---|---|---|
| 6 × 10in | 5 7/8 × 8 3/4in | 3/16in2.4 mil |
Sources: Uline. Checked October 2026.
Uline’s #0 and a small boxed item are filled in. Enter your mailer’s outside and usable sizes and your item; each check follows a rule or figure on this page.
Enter the outside width × length with the flap left off, as US sellers list mailers; bubble mailers also carry a usable size on the maker’s sheet. The filled height below is the item’s thickness, plus 3/16 in of bubble lining on each side for a bubble mailer.
At 4 × 7 in the item is within the maker’s usable 5.875 × 8.75 in, and width + thickness, 5 in, stays within the usable width, so the tube closes round it.
Uline’s #0 is filled in: 6 × 10 in outside, 5 7/8 × 8 3/4 in usable. Uline’s outside size includes the folded flap and leaves out the seams.
Length 10 in plus width 6 in, each rounded down to the quarter inch, make 16 in: tier 0.1 for Ground Advantage and Priority Mail soft packs.
Bubble mailers count as soft packs and are measured outside: the #0 adds up to 16 in, tier 0.1.
Filled, the mailer is 10 × 6 × 1.375 in. UPS adds Additional Handling to soft packs over 18 × 14 × 6 in, FedEx over 18 × 13 × 5 in (longest side, second side, height): neither applies.
Uline lines its mailers with 3/16 in bubble, so the filled height is the item plus 3/8 in.
Selling bubble mailers? Photograph one, mark the outside and usable sizes and the bubble in SizeMarker and send it with your quote.
Mark a photoInches, width × length. Uline’s and IPG’s usable size follows the arrow; Sealed Air publishes the outside size only.
| No. | Uline: outside → usable | IPG XPAK: size → usable | Sealed Air TuffGard |
|---|---|---|---|
| #000 | 4 × 8 → 3 7/8 × 6 3/4 | 4 × 8 → 4 × 7 | 4 × 8 |
| #00 | 5 × 10 → 4 7/8 × 8 3/4 | 5 × 10 → 5 × 9 | 5 × 10 |
| #0This page | 6 × 10 → 5 7/8 × 8 3/4 | 6.5 × 10 → 6.25 × 9 | 6 × 10 |
| #1 | 7 1/4 × 12 → 7 1/8 × 10 3/4 | 7.25 × 12 → 7 × 11 | 7.25 × 12 |
| #2 | 8 1/2 × 12 → 8 3/8 × 10 3/4 | 8.5 × 12 → 8.25 × 11 | 8.5 × 12 |
| #3 | 8 1/2 × 14 1/2 → 8 3/8 × 13 1/4 | 8.5 × 14.5 → 8.25 × 13.5 | 8.5 × 14.5 |
| #4 | 9 1/2 × 14 1/2 → 9 3/8 × 13 1/4 | 9.5 × 14.5 → 9.25 × 13.5 | 9.5 × 14.5 |
| #5 | 10 1/2 × 16 → 10 3/8 × 14 3/4 | 10.5 × 16 → 10.25 × 15 | 10.5 × 16 |
| #6 | 12 1/2 × 19 → 12 3/8 × 17 3/4 | 12.5 × 19 → 12.25 × 18 | 12.5 × 19 |
| #7 | 14 1/4 × 20 → 14 1/8 × 18 3/4 | 14.25 × 20 → 14 × 19 | 14.25 × 20 |
Sources: Uline · IPG · Sealed Air
| Item | What the sheet says |
|---|---|
| Usable against outsideUline, IPG, JiaroPack | Length 1 in shorter at IPG and JiaroPack, 1 1/4 in at Uline; width 0 to 1/4 in narrower |
| What to compareJiaroPack; EcoEnclose | Size the item against the usable size, not the outer size (JiaroPack); EcoEnclose names its bubble mailers by the usable size |
| JiaroPack | #0: 6 × 10 in outside, holds up to 6 × 9 in; #5: 10.5 × 16 → 10.5 × 15 in |
| EcoEncloseUsable, then outer | 4 × 6.75 in in a 4.875 × 10.0 in mailer; 6.5 × 8.75 in in 7.375 × 12.0 in; 10.5 × 14.75 in in 10.5 × 15 in |
| Uline lining and filmS-7544 page | 3/16 in bubble lining; 2.4 mil film; outside sizes include the folded flap, widths leave out the seams |
| The number is a conventionUline; IPG; 3M | Uline calls its numbers the industry standard, yet #0 is 6 × 10 at Uline and Sealed Air, 6.5 × 10 at IPG, and 3M’s Size 0 is a 6 × 9 in interior |
| European codesVP aroFOL poly, inside mm | 2/B 120 × 215, 3/C 150 × 215, 4/D 180 × 265, 7/G 230 × 340, 8/H 270 × 360, 10/K 350 × 470 |
| SeamsVP aroFOL | 10 mm sealed edges, so the outside is 20 mm wider than the inside (140 against 120 mm on a 2/B) |
| EcoEnclose build | Nine film layers, 60% recycled plastic of which 35% post-consumer; 1/16 in thick, flat |
| 3M ScotchOffice Depot | Size 0: interior 6 × 9 in; made from 50% recycled content |
Sources: Uline · IPG · JiaroPack · EcoEnclose · Uline · Sealed Air · Office Depot · VP Group
| Rule | What it says |
|---|---|
| USPS soft packDMM 283.1.3 | Padded envelopes are measured like poly bags: outside length + width, each rounded down to 1/4 in |
| Tiers from 12 July 2026Ground Advantage and Priority Mail | Up to 21 in tier 0.1, 27 in 0.2, 31 in 0.3, 34 in 0.4, 36 in 0.5; longest side 22 in, 20 lb |
| Numbered sizes in tiersOur calculation, Uline outside sizes | #000 12 in and #0 16 in: 0.1; #2 20 1/2 in: 0.1; #4 24 in: 0.2; #5 26 1/2 in: 0.2; #6 31 1/2 in: 0.4; #7 34 1/4 in: 0.5 |
| Filled heightUline lining; our calculation | Item thickness plus 3/16 in of bubble on each side, 3/8 in in all |
| UPS soft packsTariff of 17 April 2026 | Bubble mailers over 18 in long, 14 in on the second side or 6 in high: Additional Handling |
| FedEx soft packsService Guide 2026, US domestic | Over 18 in, 13 in or 5 in: Additional Handling |
| UK Plastic Packaging TaxHMRC | A kraft-faced mailer counts as plastic when plastic is the heaviest material in it; 30% recycled plastic or more is not taxed |
Sources: USPS (Federal Register) · USPS (Federal Register) · Uline · Uline · UPS · FedEx · HMRC (gov.uk)
6 × 10 in outside at Uline and Sealed Air, 6.5 × 10 in at IPG. Inside, Uline’s holds 5 7/8 × 8 3/4 in, IPG’s 6.25 × 9 in and JiaroPack’s 6 × 9 in.
Outside, at Uline: #000 4 × 8, #00 5 × 10, #0 6 × 10, #1 7 1/4 × 12, #2 8 1/2 × 12, #3 8 1/2 × 14 1/2, #4 9 1/2 × 14 1/2, #5 10 1/2 × 16, #6 12 1/2 × 19 and #7 14 1/4 × 20 in. IPG’s #0 is wider, so check the maker.
About 1 to 1 1/4 in shorter and up to 1/4 in narrower at Uline, IPG and JiaroPack. Compare your item with the maker’s usable size before you buy.
Uline’s has a 3/16 in bubble lining inside 2.4 mil film; EcoEnclose gives its mailers as 1/16 in thick, lying flat.
Letter codes with inside sizes in millimetres: VP’s aroFOL runs from 2/B, 120 × 215 mm, to 10/K, 350 × 470 mm, with 10 mm sealed edges.
Buyers ask what each number means in your range, the outside and the usable size, the bubble height and the film thickness, the seams and the flap, the recycled share and how many come in a case. Mark the real mailer, its usable area and the bubble on your own photo in SizeMarker, as in the picture at the top, and send one product card for WhatsApp or WeChat.
Working out the postage
Volumetric weight calculatorDimensional weight of a filled bubble mailer
