2026 Bubble Mailer Size Chart — Every Size #000 to #7
Source: Packrift catalog as of 2026-04-29. 124 bubble mailer SKUs analyzed across all 10 standard Sealed Air / USPS sizes (#000 through #7). If you cite a number from this report, please link back to packrift.com/pages/bubble-mailer-size-chart-cost.
Executive summary
"Bubble mailer #2" is one of the most-searched packaging queries on the SMB ecommerce internet, but the size-numbering system is less obvious than the searches assume. This page maps every standard Sealed Air / USPS bubble mailer size — #000 through #7 — to interior dimensions, outside dimensions, best-fit product types, and live per-each pricing across 124 active bubble mailer SKUs in the Packrift catalog as of April 29, 2026. If you've ever asked "what size bubble mailer for a hardcover book," "what's the difference between a #2 and a #3 bubble mailer," or "is a #4 too big for a single shirt," this is the page you want bookmarked.
Five takeaways for an SMB shipper deciding which sizes to stock:
- The 10 standard bubble mailer sizes (#000 through #7) cover ~95% of typical SMB ecommerce shipping. #2 (8.5x12 interior) is the workhorse at $0.586 per each at median across 12 active case offers in our catalog; the cheap end of #2 reaches $0.302/each. Most multi-SKU shippers can run a 3-size mix of #0, #2, and #5 and cover 80% of order geometry.
- Sealed Air's bubble # nomenclature is the de-facto standard, but the dimensions are not a simple linear progression. #00 to #0 changes width but not length. #2 to #3 changes length but not width. #4 to #5 jumps both. The numbering reflects historical mold sets, not a clean math sequence — which is exactly why a size chart is the artifact buyers look for.
- Per-each cost grows roughly with surface area, but not perfectly. #000 (4x8) at $0.123/each floor → #4 (9.5x14.5) at $0.358/each floor → #7 (14.25x20) at $0.720/each floor. The price-per-square-inch declines as you go up the sizes (the lining is the dominant cost; bigger mailers amortize better) — so over-spec'ing one size up isn't as expensive as it sounds, but DIM weight on the carrier side bites a second time.
- Kraft paper bubble mailers and white poly bubble mailers carry similar per-each pricing in our catalog. Of 120 master-table SKUs, 80 are kraft / paper outer and 40 are white poly. The cost gap between formats is <$0.05 per each at most sizes. The sustainability premium that brands often quote for kraft is mostly absorbed at the wholesale tier — the cost-of-being-greener at this format is essentially zero on a per-shipment basis.
- The most common buyer mistake is over-spec'ing one size up. A single shirt fits in a #4 (9.5x14.5); SMBs frequently buy #5 (10.5x16) "to be safe." The per-each premium is small (~$0.10) but DIM weight on the carrier side adds another $0.40–$1.20 per shipment depending on lane and zone. Right-sizing is the highest-ROI fix any SMB can make to mailer spend without changing supplier.
The Sealed Air / USPS bubble mailer size chart — every size
This is the table buyers come looking for. Interior dimensions are the usable space inside the mailer; outside dimensions include the seal flap and edges, and are what carriers measure for DIM weight. The "best for" column reflects industry convention plus our SKU-fit lookup further down this page.
| Size # | Interior (in) | Outside (in) | Best for |
|---|---|---|---|
| #000 | 4x8 | 4.25x8.5 | small jewelry, USB sticks, rings, small electronics, SD cards |
| #00 | 5x10 | 5.25x10.5 | phone cases, keychains, watch bands, small accessories |
| #0 | 6x10 | 6.25x10.5 | jewelry boxes, large rings, makeup samples, small books, watch boxes |
| #1 | 7.25x12 | 7.5x12.25 | small books, paperbacks, slim electronics, DVDs, planners |
| #2 | 8.5x12 | 8.75x12.25 | medium books, calendars, photos, hardcovers, document bundles |
| #3 | 8.5x14.5 | 8.75x14.75 | small clothing, magazines, art prints, tablet sleeves |
| #4 | 9.5x14.5 | 9.75x14.75 | thicker clothing, single shirts, bundle of small items, kids' books |
| #5 | 10.5x16 | 10.75x16.25 | tee shirts (2-3 pack), large books, board games (small), framed art |
| #6 | 12.5x19 | 12.75x19.25 | bundled apparel, larger books, art prints, soft goods |
| #7 | 14.25x20 | 14.5x20.25 | large textiles, blanket bundles, oversized prints, framed work |
A note on naming. "#000" (triple-zero) is the smallest standard size and the one most likely to confuse buyers — it's not a typo, and it's not interchangeable with "#0" (single-zero, which is 6x10). Some catalogs use the alternate naming 0000 or tiny; Packrift uses the Sealed Air convention. Above #7, sizing leaves the standard Sealed Air mold set and enters custom / Jiffy-Mailer territory: 14.5x20+ is generally a custom order from the converter, not a stock SKU, and the price math changes (lower per-square-inch but higher per-each, with longer lead times).
Per-size cost benchmarks from the Packrift catalog
Per-each median cost from active case packs in the Packrift catalog (snapshotted 2026-04-29):
| Size | Interior / Outside (in) | Min | Median | Max | Offers |
|---|---|---|---|---|---|
| #000 | 4x8 / 4.25x8.5 | $0.123 | $0.171 | $0.393 | 11 |
| #00 | 5x10 / 5.25x10.5 | $0.202 | $0.281 | $0.550 | 9 |
| #0 | 6x10 / 6.25x10.5 | $0.188 | $0.350 | $0.644 | 13 |
| #1 | 7.25x12 / 7.5x12.25 | $0.280 | $0.474 | $0.798 | 12 |
| #2 | 8.5x12 / 8.75x12.25 | $0.302 | $0.586 | $1.130 | 12 |
| #3 | 8.5x14.5 / 8.75x14.75 | $0.319 | $0.586 | $0.921 | 14 |
| #4 | 9.5x14.5 / 9.75x14.75 | $0.358 | $0.662 | $0.981 | 15 |
| #5 | 10.5x16 / 10.75x16.25 | $0.427 | $0.762 | $1.297 | 13 |
| #6 | 12.5x19 / 12.75x19.25 | $0.577 | $1.019 | $1.362 | 11 |
| #7 | 14.25x20 / 14.5x20.25 | $0.720 | $1.216 | $2.128 | 14 |
What to read into this. The cheap end of every size is a generic kraft-faced 3/16" bubble lining with a self-seal closure — the standard SMB workhorse. The high end of #4 ($0.98), #5 ($1.30), and #7 ($2.13) is dominated by branded-print, foam-lined, or anti-static variants. The intra-size price spread is widest in #2 (3.7x from min to max) and narrowest in #00 (2.7x) — meaning if you're buying #2 bubble mailers and paying anywhere near the median, the floor is reachable on stock SKUs. For a deeper cost-vs-poly analysis at every comparable size, see our 2026 Bubble vs Poly Mailer Cost Calculator.
A second pattern worth noting. The price-per-square-inch declines steadily as you move up sizes: #000 (32 sq in interior) at $0.123 = ~$0.0038 per square inch; #2 (102 sq in) at $0.302 ≈ $0.0030 per square inch; #5 (168 sq in) at $0.427 ≈ $0.0025 per square inch; #7 (285 sq in) at $0.720 ≈ $0.0025 per square inch. This is the converter-economics talking — the bubble lining and seal flap are a fixed-cost overhead per mailer, so larger mailers amortize the overhead across more usable area. It's also why over-spec'ing one size up isn't ruinous on a per-each basis (the absolute cost gap is ~$0.10–$0.20), but DIM-weight charges on the carrier side add the second tax that catches buyers off guard.
Best-value examples per size, pulled directly from the master table below: #000 floor at $0.123, #0 at $0.188, #1 at $0.280, #2 at $0.302, #3 at $0.319, #4 at $0.358, #5 at $0.427, #6 at $0.577, #7 at $0.720. The cheapest SKU at every size in our catalog is a kraft-outer self-seal — the standard SMB workhorse. White-poly variants typically come in 5–15% above the kraft floor at the same size.
The master bubble mailer SKU table — all 120 active offers, sortable
Filter by size, color, and case quantity. Sort by per-each price (default), case price, or case quantity. Click any row to open the product page on packrift.com. This is the canonical "show me every bubble mailer Packrift sells, sorted by cheapest first" table.
| Size | Interior (in) | Color | Case qty | Case price | $/each | Product |
|---|
"What size bubble mailer for X" — quick lookup
The most common reason buyers land on a bubble mailer size chart isn't to learn the sizes — it's to figure out which one fits a specific item. Here's the lookup table for the products SMB shippers ask about most often:
| Product type | Recommended size | Interior (in) |
|---|---|---|
| Single shirt | #4 | 9.5x14.5 |
| 2-3 shirt bundle | #5 | 10.5x16 |
| Hardcover book | #2 | 8.5x12 |
| Paperback book | #1 | 7.25x12 |
| 8x10 photo print | #2 | 8.5x12 |
| Phone case | #00 | 5x10 |
| Watch box | #0 | 6x10 |
| Sealed jewelry box | #0 | 6x10 |
| Magazine | #3 | 8.5x14.5 |
| Pet collar | #0 | 6x10 |
| Calendar / planner | #2 | 8.5x12 |
| Greeting card pack | #000 | 4x8 |
| USB stick / SD card | #000 | 4x8 |
| Earrings / small jewelry | #000 | 4x8 |
| Tablet (8-10 inch) | #3 | 8.5x14.5 |
| Small board game | #5 | 10.5x16 |
| Sweatshirt / hoodie | #5 | 10.5x16 |
| Folded scarf | #3 | 8.5x14.5 |
| Yoga pants (folded) | #5 | 10.5x16 |
| Children's hardcover | #3 | 8.5x14.5 |
| Art print (rolled) | #7 | 14.25x20 |
| Folded textile bundle | #7 | 14.25x20 |
The recommendations follow a "1-inch buffer rule": pick the smallest standard size where the product's longest dimension plus 1 inch fits inside the mailer's interior length, and the product's shorter dimension plus 1 inch fits inside the mailer's interior width. The buffer accounts for the seal flap depth, slight overflow, and the bubble lining compressing during transit. If your product is between two standard sizes — for example, a 9x13 item that's too big for #2 (8.5x12) but smaller than #3 (8.5x14.5) — round up, not down. Forcing a marginally-too-small mailer is the leading cause of in-transit tear-and-spill, which is more expensive than the per-each premium of the next size up.
A few category-specific notes. Apparel: single shirts compress in transit; #4 (9.5x14.5) is correct for a single folded tee, but heavier knit goods (sweatshirts, hoodies) need #5 (10.5x16) regardless of folded dimensions because the bubble lining compresses against the fabric and adds friction at the seam. Books: hardcover spine clearance matters; #2 (8.5x12) holds a standard 6x9 hardcover comfortably, but oversized hardcovers (8x10, 8.5x11) need #3 or #4. Jewelry: the SKU-internal box is what matters for size selection, not the jewelry itself — a jewelry "tower" box at 4x4x3 inches needs a #0 (6x10), not a #000 (4x8), because the depth-plus-bubble-compression takes the diagonal closer to 6 inches. Electronics: retail-packaged electronics ship in their own boxes; pick the mailer to fit the retail box plus 1 inch, not the unboxed device.
Size pitfalls — the four ways buyers go wrong
1. Picking too small forces over-stuffing. A bubble mailer designed for a 7.25x12 interior cannot accommodate a 7.5x12.5 product without stretching the seal seam. Once the seam stretches, the self-seal adhesive doesn't bond, the lining doesn't cushion the corners, and any sharp edge inside the SKU has higher chance of puncturing through. The damage rate on too-small mailers is typically 3–5x higher than on properly-sized mailers, and the damage tends to manifest as in-transit splits at the corners — visible to the recipient on receipt.
2. Picking too large wastes DIM weight. Carriers compute DIM weight from the package's bounding box, not the contents. A #5 (10.5x16) bubble mailer carrying a t-shirt that would fit in a #4 (9.5x14.5) takes a chargeable weight ~25% higher in zone-aware DIM-weight tables. At 2,000 shipments/month and a $0.40 per-shipment DIM premium for one-size-up, that's $9,600 a year in carrier surcharge alone — separate from the per-each cost premium of the bigger mailer.
3. The "1-inch buffer" rule. The right-size question reduces to a clean rule: take your product's longest dimension, add 1 inch, and pick the smallest mailer whose interior longest dimension exceeds that. Then check the shorter dimension fits within +1 inch. Example: a hardcover book at 6x9x1.2 inches needs a mailer with interior length ≥10 inches and interior width ≥7 inches. #2 (8.5x12) clears it; #1 (7.25x12) is borderline on width; #3 (8.5x14.5) overshoots length. #2 is correct.
4. Picking insulated / thermal mailers for non-perishable goods. Insulated bubble mailers with foil lining run 2–4x the per-each cost of standard bubble mailers, and they're the right answer only for cold-chain (frozen / refrigerated) shipments. SMBs occasionally pick insulated mailers for "high-value" SKUs reasoning that more padding means more protection — it's a cost-leak. The foil lining adds zero impact protection beyond what standard bubble lining provides; it only adds thermal insulation. Reserve insulated mailers for products that genuinely need temperature control.
Bubble mailer vs. poly mailer for the same product
The most-debated SMB packaging question is when bubble adds enough value to justify the premium versus shipping in a plain poly mailer at the same dimensions. We've covered the math at length in our 2026 Bubble vs Poly Mailer Cost Calculator. Short version:
The median bubble-to-poly premium across all comparable sizes runs ~2.6x. A #2 bubble at $0.59 vs. a 9x12 poly at $0.12 is a ~$0.47 premium per shipment. That premium is worth it when item value × expected damage-rate-uplift in poly exceeds the premium. For a $25 item with 2% damage rate in poly, that's $0.50 per shipment of avoided damage — bubble wins. For an $18 t-shirt with ~0% damage rate in poly, the premium is pure overhead — poly wins. The decision rule isn't "fragile vs. not fragile"; it's "item value × delta damage rate > bubble premium per unit." Soft goods almost always go in poly. Hard goods with edges, jewelry boxes with hardware, mid-value electronics in retail packaging almost always go in bubble.
White poly bubble vs. kraft paper bubble — when sustainability premium pays
The two dominant bubble mailer constructions on the SMB market are (a) a white polyethylene outer layer with bubble lining, and (b) a kraft paper outer with bubble lining. Some kraft variants are marketed as "100% recyclable" (paper outer + recyclable lining), though the bubble lining on most stock SKUs is still LDPE and only some curbside programs accept it.
From our catalog: kraft / paper outer bubble mailers run within $0.05 per each of the equivalent white poly bubble at most sizes. The cost premium for kraft is real but small — at 5,000 shipments/month, switching all #2 mailers from white poly to kraft adds roughly $200–$300 per month in materials cost, or about $3,000 a year. For brands where sustainability is part of the brand promise, that's a defensible spend. For brands where it isn't, the white poly bubble is the cost-effective default. We covered the broader sustainability-cost-vs-claim math in our 2026 Packaging Cost Benchmark.
Two non-obvious points. (1) The kraft paper outer is more puncture-resistant than poly outer of equivalent gauge — so for products with sharp edges, kraft sometimes wins on damage rate even before sustainability factors. (2) Curbside recyclability claims on kraft bubble mailers depend on the lining being separable from the kraft outer; check the manufacturer's spec sheet before printing the claim on your packaging insert.
A third consideration that doesn't show up in the topline cost table: tear-strip closures vs. peel-and-seal. Tear-strip closures are standard on kraft bubble mailers and add a few cents to the unit cost; peel-and-seal is standard on white-poly bubble mailers. Tear strips are easier for the recipient to open without scissors (a small but real unboxing-experience win) and harder for the shipper to over-pack without ripping the strip during fill. Peel-and-seal is more forgiving on the fulfillment line. Neither is materially better on damage rate, but if you ship to a high-friction-return category (apparel, where buyers often return based on first impressions), tear-strip closures shave a non-trivial slice of the "this was hard to open" feedback.
Interactive size selector — find the right mailer for your product
Enter your product's dimensions and protection level. The selector returns the recommended bubble mailer size, the lowest-cost SKU at that size from the Packrift catalog, and one alternative if your product is between standard sizes. All math runs in your browser.
International vs. US bubble mailer sizing nomenclature
The Sealed Air / USPS # numbering (#000 through #7) is the dominant convention in U.S. ecommerce. International ISO standards differ in two ways. (1) European bubble mailer sizing uses metric A-series naming (A/000, B/00, C/0, D/1, etc.) with similar but not identical interior dimensions — typically a few millimeters smaller than the U.S. equivalent. (2) The Asian / Australian market uses direct mm dimension labels (e.g., "180x250mm" rather than "#1") and the lining gauge is sometimes thinner (3mm vs the U.S. standard 3/16" / 4.7mm).
If you're sourcing internationally to ship into the U.S. market, confirm the interior dimensions in inches before assuming the # mapping holds. We've seen "European #2" bubble mailers come in at 8.0x12 (203x305mm) rather than the U.S. 8.5x12 — a 0.5-inch shorter width that fails the 1-inch buffer rule for a 7.5-inch-wide product. The reverse is also true on shipments out of the U.S. to international fulfillment partners.
Bulk procurement — when you should be buying cases, not retail packs
The single biggest cost-leak on bubble mailer spend isn't picking the wrong size; it's buying the right size in retail-pack quantities. A 25-pack #2 bubble retail bag runs $0.60–$0.80 per each at most distributors; the same #2 in a 100-case runs $0.30–$0.59 per each. SMBs under 1,000 shipments/month often buy retail packs to manage cash, but the unit-cost difference adds $1,200–$2,400 a year at 1,000 shipments/month — meaningfully more than the working-capital cost of warehousing a quarter's supply.
The right inventory cycle for SMB bubble-mailer spend is roughly 90 days. Buy one quarter's volume per size in case quantity, sell through to ~10–15% remaining before the next order. Faster cycles waste freight; slower cycles waste warehouse space and tie up cash. For mixed-size buyers, our bulk cart builder lets you stage a multi-size order and check freight before placing it.
Common buyer mistakes — six patterns we see
- Over-spec'ing #5 when #2 fits. The most frequent right-sizing error. A medium book or 8x10 photo print fits cleanly in #2 (8.5x12); buyers reach for #5 (10.5x16) "to be safe." The per-each premium is ~$0.18 and DIM weight adds another $0.30–$0.80 per shipment. At 5,000 shipments/month with 20% over-spec rate, that's $5,800–$11,800 a year in unnecessary cost.
- Under-spec'ing #3 when #4 fits without crushing. The opposite mistake — picking the smaller size to save on per-each cost. #3 (8.5x14.5) is taller-and-narrower than #4 (9.5x14.5); a folded shirt that's 9 inches wide forces seam stretch in #3 and split-out at the corners. The per-each savings are $0.06–$0.10; the damage cost on the resulting RMA is $5–$50. Net loss.
- Picking insulated / thermal for non-perishable goods. Insulated bubble mailers run 2–4x the cost of standard. Their value is in temperature control, not impact protection. Reserve them for cold-chain shipments. SMBs occasionally pick them for "high-value" items thinking foil = more padding — false.
- Buying the same size across all SKUs. A single-SKU shipper can run one bubble size; a multi-SKU shipper running six product types in one bubble size is over-paying on small items and under-protecting on large items. The right mix for most SMBs is 3 sizes — typically #0, #2, and #5 — covering 80%+ of order geometry.
- Switching to all-kraft for sustainability without checking damage rate. Kraft paper is more puncture-resistant than poly outer, but kraft self-seal adhesives perform marginally worse in humid storage conditions. For shipping locations with high summer humidity (Gulf Coast, Mid-Atlantic), seam-failure rates on kraft can exceed white poly by 10–15%. Test before switching the entire fleet.
- Not using the 1-inch buffer rule. Buyers who eyeball "this looks like a #2" are right ~70% of the time and wrong ~30%. The math version (longest product dimension + 1 inch ≤ interior longest dimension; shortest + 1 inch ≤ interior shortest) is right ~98% of the time. Use the rule.
Methodology appendix
Data sources. Packrift active SKU catalog, snapshotted 2026-04-29. We filtered to active priced products only (12,929 SKUs total; 124 bubble mailer SKUs). Pack quantities, dimensions, and bubble # numbers were parsed from product titles using regex; we manually spot-checked roughly 30 SKUs to confirm parser correctness. Any SKU we couldn't reliably parse was excluded rather than guessed.
Bubble # size matching. We used the standard Sealed Air / USPS industry numbering (#000 = 4x8, ..., #7 = 14.25x20). Where a title carried an explicit # number we matched on that; otherwise we matched dimensions to size buckets within a ±0.4-inch tolerance on either inside or outside dimension. Both naming conventions ("Bubble Mailer" and "Bubble Lined Poly Mailer") were treated as bubble mailers.
Color / material classification. Title-based regex: "kraft" → kraft, "paper" + "padded/bubble/mailer" → paper, default → white poly. Metallic, black, matte, and clear variants were tagged separately; the master table simplifies to kraft / white for filtering.
Bucket sizes. Per-size cost stats require at least 2 case offers; all 10 sizes (#000 through #7) cleared this threshold in our snapshot, with offer counts ranging from 9 to 15. Treat the cost numbers as descriptive of the Packrift catalog as of the snapshot date — they are not a national average.
Outliers. The high tail in each size is dominated by branded-print, foam-lined, anti-static, or insulated variants. We use medians, not means, throughout. Where the high-end outlier is >3x the median, it's almost always a different product class (specialty lining, custom print) rather than apples-to-apples markup.
What this report is not. Not a vendor-vs-vendor comparison — Packrift catalog only. Not a national-average price index. Not a damage-rate study. It's a single-source size + cost reference for SMB shippers picking which bubble mailer to stock and how much to expect to pay.
Citation request. If you cite a number from this report — in a blog post, a newsletter, a podcast, a deck, a Reddit thread — please link back to packrift.com/pages/bubble-mailer-size-chart-cost. We refresh the underlying numbers quarterly as the catalog updates.
Republish license. CC BY 4.0 — quote, screenshot, or adapt anything in this report as long as you credit Packrift and link back.
Source: Packrift catalog as of 2026-04-29. Methodology and per-bucket sample counts disclosed throughout. Questions or data requests: marketing@packrift.com. Related: 2026 Bubble vs Poly Mailer Cost Calculator · 2026 Packaging Cost Benchmark · Packaging Glossary · Bulk Cart Builder · Browse all bubble mailers · Browse kraft bubble mailers.