Bubble Mailers Size Chart: Dimensions & Use Cases

How Do Bubble Mailer Sizes Work?

Bubble mailer sizes are built around a simple size-and-code system, so matching a product to the right envelope comes down to internal dimensions. Picking the wrong size costs more than it should: an oversized mailer wastes postage and protective bubble film, while an undersized one leaves the contents exposed to knocks in transit. Many sellers stick with one all-purpose size out of habit, even when their product range would ship more safely and cheaply across several.

The confusion often shows up when shoppers search by inch-based names like a 6x10 or 4x8 mailer, terms common in US listings that don't map cleanly onto the UK's millimetre-based Jiffy codes. 

The closest UK match is sometimes a size larger or smaller than expected, which matters once bubble lining thickness is added to a Royal Mail postage calculation. Getting the conversion right the first time avoids underpaid postage, returned parcels, and mailers that don't actually protect what's inside.

Globe Packaging stocks the full Jiffy range from JL000 through JL8, so switching between sizes as your product mix changes doesn't mean switching suppliers. Every size ships from the same UK depot with next-working-day delivery on qualifying orders, keeping the sizing decision the only thing you have to think about.

Bubble Mailer Dimensions

1. Small Sizes (JL000–JL1)

JL000 bubble mailers are best for small items, such as earrings or SD cards. 

The small end of the Jiffy range covers four sizes: JL000 (Size A) at 90 x 145 mm, JL00 (Size B) at 115 x 195 mm, JL0 (Size C) at 140 x 195 mm, and JL1 (Size D) at 170 x 245 mm. These are compact, lightweight mailers designed for products that don't take up much space but still need reliable cushioning during transit.

Despite their small footprint, these mailers offer genuine protection. The bubble lining inside absorbs impact, making them far more protective than a standard paper envelope. They're also cost-effective. Using a smaller mailer where appropriate keeps your material and postage costs down, which adds up quickly at volume.

Best Use Cases

The JL000 and JL00 are ideal for very small items like SIM cards, SD memory cards, small earrings, rings, and USB drives. The JL0 works well for items like keyrings, small cosmetics, lip balms, or single packs of trading cards. 

Step up to the JL1, and you've got enough room for items like a smartphone case, a small paperback book, folded fabric samples, and products with a bit more bulk but still well within the small mailer territory.

2. Medium Sizes (JL2–JL4)

JL2 bubble mailers can be used for small toys and accessories.

The medium range features JL2 (Size E) at 205 x 245 mm, JL3 (Size F) at 220 x 320 mm, and JL4 (Size G) at 240 x 320 mm. It covers the most commonly used bubble mailer sizes in e-commerce. These three sizes are often suitable for the vast majority of everyday products sold online.

The jump from JL2 to JL3 adds significant length (75mm), making it much more versatile for items that are flat but longer, like phone cases for larger smartphones, cosmetic sets, or stationery packs. The JL4 adds a little extra width over the JL3, giving you just enough additional room for slightly bulkier flat items without jumping to a large mailer unnecessarily.

Best Use Cases

Medium bubble mailers are typically used in most e-commerce operations. The JL2 handles products like sunglasses, folded t-shirts, small toys, and multi-pack phone accessories with ease. The JL3 is best for hardback books, tablet cases, stationery sets, and flat board games, while the JL4 (240 x 320 mm) is a good fit for A4 documents, medium-sized clothing, cosmetic bundles, and small electronics.

If you sell across multiple product categories, stocking JL3 and JL4 mailers gives you the flexibility to handle a wide range without constantly switching between sizes. Many businesses find these two sizes alone cover the bulk of their fulfilment needs.

3. Large Sizes (JL5–JL8)

JL8 bubble mailers are designed for larger products that need space and protection in equal measure.

For bigger products, the large Jiffy mailer range steps up considerably. The JL5 (Size H) measures 260 x 345 mm, and the JL6 (Size J) is 290 x 445 mm. Still in the same range, the JL7 (Size K) comes in at 340 x 445 mm, while the JL8 (Size L) measures 460 x 660 mm. 

The JL6 and JL7 are particularly popular with clothing sellers. A folded hoodie, a pair of jeans, or a lightweight jacket fits comfortably inside these sizes without being crammed in. The extra length in both the JL6 and JL7 (445 mm) is especially useful for longer flat items like rolled documents, scarves, or wall art prints that need to stay flat during shipping.

Best Use Cases

Large bubble mailers are the go-to for fashion retailers, art sellers, and anyone shipping soft goods or large flat items. The bubble lining on the JL5 through JL8 range is the same as the smaller sizes, so protection quality doesn't drop off as you go larger.

The JL8 at 460 x 660 mm is large enough to accommodate A2 posters, multiple folded garments, large cushion covers, or bulky soft goods and A1 posters when rolled or folded. 

If you're shipping anything that approaches A2 size when flat, the JL8 is the mailer to reach for. It delivers the same bubble-lined protection as the smaller sizes but at a scale that works for genuinely large products.

Full Bubble Mailer Size Chart

Match the Mailer Size to the Product with Globe Packaging

Finding the right bubble mailer is a matter of matching the size to your product. A compact JL000 or JL0 is best for jewellery and accessories. A versatile JL3 or JL4 is better suited for books and everyday e-commerce orders, while a roomy JL7 or JL8 is best for garments and large flat goods. Because the bubble lining stays consistent across the whole range, you get the same dependable protection whether you're shipping a memory card or an A1 poster.

At Globe Packaging, we make it easy for businesses to keep the right sizes on hand. We stock the complete Jiffy range in high-grade, bubble-lined quality, held in a 60,000 sq ft depot that keeps availability strong even at volume. We also offer same-day dispatch on orders placed by 4 p.m. and free next-working-day delivery across the UK mainland on qualifying orders. Shop Globe Packaging today. 

*Note: Product listings, prices, and delivery times shown are approximate and subject to change. Contact Globe Packaging for the latest information.