Industrial & logistics · Reference
The 4 × 6 in (101.6 × 152.4 mm) direct-thermal label is the universal shipping standard: USPS, UPS, FedEx, and DHL all accept it, and every thermal printer prints it. Smaller 2 × 1 to 3 × 2 in rolls handle barcodes and pricing.
Thermal shipping labels are specified width × height; 4 × 6 in (102 × 152 mm) is the dominant format across all major carriers.
| Format | Width | Height | Primary use |
|---|---|---|---|
| 4 × 6 in (standard) | 4 in (101.6 mm) | 6 in (152.4 mm) | Dominant standard — all major carriers |
| 4 × 8 in | 4 in (101.6 mm) | 8 in (203.2 mm) | International / B2B, customs & tracking |
| 4 × 4.25 in | 4 in (101.6 mm) | 4.25 in (108 mm) | Small boxes, local parcels |
| 2 × 4 in | 2 in (50.8 mm) | 4 in (101.6 mm) | Small envelopes, jewelry |
| 2 × 3 in | 2 in (50.8 mm) | 3 in (76.2 mm) | Lightweight parcels, returns |
| Carrier | Standard label | Alternates accepted |
|---|---|---|
| USPS | 4 × 6 in (Click-N-Ship default) | 4 × 4, 4 × 8, A4 / letter |
| UPS | 4 × 6 in (default) | 4 × 4, 4 × 8, 8.5 × 11 letter |
| FedEx | 4 × 6 in | 4 × 4, 4 × 8, 8.5 × 11, 8.5 × 5.5 |
| DHL | 4 × 6 in (default) | 4 × 4, 4 × 8, A5 |
Source: McAuley Labels — Does a Shipping Label Have to Be 4×6? Full Carrier Guide
| Use | Size | Typical application |
|---|---|---|
| Barcode / SKU | 2 × 1 in (50.8 × 25.4 mm) | Barcodes, SKU, small product ID |
| UPC / SKU (DYMO) | 2.25 × 1.25 in (57 × 32 mm) | UPC and SKU labels |
| Address | 3 × 1 in (76.2 × 25.4 mm) | Address & mailing labels |
| Product / price | 3 × 2 in (76.2 × 50.8 mm) | Product labels, price tags, bin labels |
| Food / info | 4 × 2 in (101.6 × 50.8 mm) | Food container & product info labels |
A spec table only helps if the buyer reads it. Many don't — shoppers routinely try to judge a product's size straight from the images, and wrong size or fit is the most-cited reason things get returned. The fix is to mark the real dimensions on the photo itself, where the buyer is already looking.
SizeMarker snaps dimension lines to the shipping label's edges and exports at Amazon or Alibaba size, so the measurement is accurate and legible — not a guess typed over the picture. That answers the size question up front and cuts pre-sale questions and size-driven returns.
Related: Industrial spec diagram maker · Product spec sheet maker · Best tools to add dimensions to product photos · Ecommerce returns & size statistics
It is 4 × 6 inches (101.6 × 152.4 mm) — the direct-thermal format accepted by USPS, UPS, FedEx, DHL, Amazon, and Shopify, and printed by every thermal label printer.
No, but 4 × 6 in is the most widely accepted. UPS also allows 4 × 6.25 in, FedEx 4 × 6.75 in (with doc tab) and 4 × 8 in, and all carriers accept letter/A4 as a fallback.
Almost. 4 × 6 in equals 101.6 × 152.4 mm, while ISO A6 is 105 × 148 mm — slightly wider and shorter. The 100 × 150 mm size is effectively interchangeable with 4 × 6.
Any 4-inch direct-thermal printer: the DYMO LabelWriter 4XL (4 in print width), Zebra and Bixolon desktop units, plus Rollo and Munbyn. No ink, toner, or ribbon is needed.
Roll labels load into a printer's compartment and suit desktop printers; fanfold labels stack flat in boxes (e.g. 5,000/box) and feed from behind for high-volume warehouse printing.
Every figure on this page is traced to a named source, linked under each table. Standard sizes come from published standards and established industry references; where a size is a typical range or varies by manufacturer, we say so. Sizes vary by region, model and revision — treat these as the standard reference, and confirm the exact spec of the item you are selling.
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