Most online sellers don't need twenty box sizes. You just need a small stash that covers the orders you actually ship, without turning your shelf into a warehouse. Five formats handle the majority of what moves through Etsy, eBay, Vinted, Depop, and Mercari: a thin mailer, a small box, a medium box, a flat garment box, and a large box for bulkier items.

Keep an oversized option only if your catalog genuinely needs it. Oversized boxes take up space and can push parcels into expensive carrier tiers.

The 5 formats and what fits inside

Box nameL×W×H (cm)L×W×H (in)Best forCarrier tier match
Mailer30×20×511.8×7.9×2.0Jewelry, patches, prints, small accessoriesInPost Paczkomat A / USPS Small Flat Rate / Royal Mail Large Letter
Small25×20×159.8×7.9×5.9Books, mugs, candles, accessories, small toysInPost Paczkomat A or B / USPS Small-Medium Priority / DHL Paket S
Medium35×25×2013.8×9.8×7.9Bundles, shoes, cosmetics sets, small home goodsInPost Paczkomat B or C / USPS Medium Flat Rate / DHL Paket M
Garment45×35×1017.7×13.8×3.9Flat clothes, scarves, jerseys, lightweight textilesInPost Paczkomat B / Evri small parcel / Royal Mail Small Parcel
Large50×40×3019.7×15.7×11.8Boots, coats, bedding, larger home goodsInPost Paczkomat C / DHL Paket M-L / UPS or FedEx Ground
Oversized60×50×4023.6×19.7×15.7Bulky bundles, lampshades, large decorOften courier-only / DHL upper tiers / UPS or FedEx DIM weight

These are practical starting sizes. Match them to your products, test with realistic padding, and verify against the carrier tiers you use most.

Pack for Etsy: Protect the presentation

Etsy sellers often ship handmade pottery, candles, prints, or jewelry. Don't measure just the finished product. Measure after the gift wrap, tissue, product card, inner box, and protective padding are included.

For fragile items, a box-in-box method is worth it—wrap the item, place it in a snug inner box, then surround that with padding inside the shipping box. For prints, use a rigid mailer. A flat mailer that saves $0.50 on postage isn't a bargain if it bends in transit.

Pack for Vinted and Depop: Consistency wins

Clothing is forgiving, but consistent dimensions matter for label accuracy. Fold garments into the same footprint every time, then choose a mailer or garment box that fits the folded size reliably.

Vacuum bags reduce volume but create irregular shapes that are harder to measure and sometimes harder for scanners to read. Use marketplace flat-shipping presets carefully. Take a quick photo of the packed item with the label visible before drop-off—it helps if there's a dispute later.

Pack for eBay: Handle variety

eBay catalogs vary wildly. Trading cards today, camera lenses tomorrow. If you offer calculated shipping, inaccurate dimensions mean you're undercharging. If you offer free shipping, oversized boxes quietly eat your margin.

USPS Flat Rate works well for dense items that nearly fill the box—books, tools, compact electronics. It's often a poor choice for light bulky goods, where a weight-based service costs less. Add room for corner protection when the item is expensive.

Test before buying bulk boxes

Test your products in the 3D Packing Calculator before committing to a 500-box order. Enter the item dimensions, add realistic padding, and see how they fit. The calculator shows the smallest practical box and the carrier tiers that can handle it.

If you sell bundles, test multi-item configurations too. Your box stash should support the orders you actually ship.

Where to source boxes

Bulk packaging suppliers generally beat marketplace prices. In Europe, Rajapack and Packhelp are solid. In the US, check Uline, The Boxery, or EcoEnclose. Compare the delivered cost—shipping empty boxes isn't cheap.

Reused boxes work great when appearance matters less. Local stores often have clean boxes before recycling pickup. Just remember to remove all old labels and barcodes completely.