Choose the 4 × 6 in label size, or 100 × 150 mm, in the print dialog and keep the scale at 100%. The label prints edge to edge, one label per print.
Where your label is after you pay
Paying opens your label on its own page in a new browser tab, titled Your shipping label. Print from that page: it lays the label out at its real size for whatever paper the printer holds, and it stays available, so the label can be printed again later.
- If the browser blocks the new tab, the confirmation screen has the same Print Label button and a link to the page.
- The email Your SMKlog shipping label carries an Open and print your label link to the same page, so any device can print it.
- Signed in with the email address you paid with, every order and its label is under My orders.
- USPS labels get a second view on the page, Show at the Post Office, with a QR code that a Post Office counter or self-service kiosk that prints labels can scan to print the label for you. Use either the code or a printed label, not both.
On a 4 × 6 thermal label printer
- Set the label size onceInstall the printer the way its maker describes, load 4 × 6 labels and choose the 4 × 6 in size in the printer settings. Many drivers list it as 100 × 150 mm; either works. If the printer asks for a calibration after a new roll, run it so the printer finds the gap between labels.
- Open the label page and press Print labelFrom the tab that opened after payment, from the link in the label email, or from My orders.
- Check four settings in the print dialogPrinter: your label printer. Paper size: 4 × 6 in or 100 × 150 mm. Layout: portrait. Scale: 100%, which Chrome calls Default. If the dialog offers margins, choose None.
- Print one and measure itFour inches across on 4 × 6 stock means every setting is right.
On paper 5 inches wide or narrower the label page drops its margin and fits the label to the paper, so it runs edge to edge and nothing spills onto a second label. 100 × 150 mm stock is a hair smaller than 4 × 6 inches; there the label is scaled to 3.94 × 5.91 inches, 1.6% smaller and the same shape.
What prints on each paper size
We printed the label page to each paper size and read where the label landed, using a test image the size of a real USPS label: 1,200 × 1,800 pixels, exactly 4 × 6 inches at 300 dots per inch.
| Paper size in the print dialog | Label printed | Where it sits |
|---|---|---|
| 4 × 6 in label | 4.00 × 6.00 | Edge to edge, one label |
| 100 × 150 mm label | 3.94 × 5.91 | Edge to edge, one label |
| US Letter, 8.5 × 11 in | 4.00 × 6.00 | 0.25 in from the top and left edges |
| A4 | 4.00 × 6.00 | 0.25 in from the top and left edges |
The calculator’s own Print Label button after payment and its Open Label page print the same way.
On letter paper, no label printer
A label printer is a convenience, not a requirement. On letter or A4 paper the page prints the label at full size in the top-left corner, a quarter inch in from the top and left edges, so two straight cuts, along the label’s right side and bottom, free it; the narrow white strip left on the other two sides does no harm. The quarter inch is there because most desktop printers cannot mark the outer edge of a sheet, and the label’s border runs right to the edge of the label.
Keep the scale at 100% and tape the label flat on the largest side of the box.
From a phone
- iPhone, in Safari. Print label opens the iPhone print screen. Choose your printer; the page uses the same print layout as on a computer.
- iPhone, with SMKlog added to the Home Screen. An app opened from the Home Screen cannot print a page, so Print label opens the Share menu instead, with the label as a PDF laid out on a letter-size page. That suits a letter printer. For a 4 × 6 label printer, open the label from the link in your label email, which opens in your browser, or use Download and print the file from the printer’s own app.
- Android, in Chrome. Print label opens the Android print screen. A printer appears there once its print service is installed, often the maker’s own app; then choose the 4 × 6 paper size.
- Printer apps. Download saves the label file: an image for most labels, a PDF for some UPS and FedEx labels. The image has the label’s own 2:3 shape, so in the app choose the 4 × 6 size and let the image fill it; nothing is cropped or stretched.
When the label comes out wrong
Reprinting costs nothing: the label you paid for is the same file every time. The usual misprints on a label printer, and what each one means:
| What came out | Why | Fix |
|---|---|---|
| Label shrunk, or cut off at the right and bottom | The print dialog still says Letter while the printer holds 4 × 6 labels | Choose 4 × 6 in or 100 × 150 mm as the paper size |
| A second, almost blank label after each one | The label size in the printer settings does not match the roll, or the printer has lost the gap between labels | Match the size to the roll and run the printer’s calibration |
| Label split across two labels, or sideways | Layout set to landscape | Choose portrait |
| Blank label | Roll loaded upside down: direct thermal stock darkens only on its coated side | Turn the roll over and check the stock is direct thermal |
| Grey or patchy barcode | Print darkness set low, or labels aged by heat or sunlight | Raise darkness, sometimes called density, in the printer settings |
| A date and a web address along the edges | Browser headers and footers switched on | Turn off headers and footers in the print dialog |
| Open label to print instead of a Print label button | This label came as a PDF, which a web page cannot print for you | Open it and print from the PDF viewer at actual size, 4 × 6 paper |
Label printing questions
Does SMKlog work with thermal label printers?
Yes. USPS, UPS and FedEx labels from SMKlog are 4 × 6 inches and print from the label page to any printer your computer or phone can print to, including 4 × 6 thermal label printers. On 4 × 6 stock the label prints edge to edge; on 100 × 150 mm stock it is scaled to 3.94 × 5.91 inches so it stays on one label.
What paper size should I choose for a shipping label printer?
The size of the labels loaded in it: 4 × 6 in, which many drivers call 100 × 150 mm. Keep the scale at 100% and the layout portrait. With a letter-size setting on a label printer, the label comes out shrunk or cut off.
Can I print an SMKlog label without a label printer?
Yes. On letter or A4 paper the label prints at full size, 4 × 6 inches, a quarter inch in from the top and left edges, so two cuts free it. For USPS labels the label page also shows a QR code that a Post Office counter or self-service kiosk that prints labels can scan to print it for you.
Can I print the same label again?
Yes, if the first copy jammed or smudged: the label page and the link in your label email stay available. Put only one copy on the parcel, and never use a label on a second parcel.