Live ZPL Label Preview

What this preview is for

Printing test labels is slow and wasteful, and it's easy to burn through a handful just fixing a misplaced coordinate. This preview lets you paste ZPL, see roughly what it will look like, and fix the obvious problems before a label comes anywhere near the printer. It redraws as you type, so you can nudge a position or a size and see the effect immediately.

It works well for layout questions. Is the text on the label? Does it overlap anything? Did the wrapping work? Is the barcode where I expect? It's also good for catching syntax slips, such as a field with no closing ^FS, since the missing text is obvious on screen.

How accurate is it?

It's an approximation, and it's worth being clear about where it falls short. The bitmap fonts, A to H, are drawn with a stand-in monospaced typeface at the right cell size, so the letter shapes differ from the real thing. Font 0 is drawn with a bold sans-serif face. Downloaded fonts can't be shown at all, because the page doesn't have them, so you see a substitute. Spacing and exact widths therefore differ a little from what the printer produces.

What it can't show at all is how your media, ribbon and heat settings affect the result. Thin strokes that look fine on screen can fade on rough stock. For anything where precise appearance matters, small text especially, treat the preview as step one and a printed sample as step two. The testing workflow article shows how to combine them.

Which commands it understands

The preview covers the commands used most for text labels: field positioning with ^FO and ^FT, fonts with ^A, ^A@ and ^CF, field data and hex escapes, field blocks, reverse print, boxes and circles, graphics and Code 128 barcodes. It reads the label size from ^PW and ^LL, and falls back to the sizes in the options if they're missing.

Other barcode types show up as dashed placeholders with a note, and unsupported commands are listed under the preview so you know what wasn't drawn. If you see a warning, it doesn't mean your ZPL is wrong, only that the preview can't draw that part.

Using the samples

The sample menu loads four small labels. The built-in fonts sample prints each font on its own line, which gives you a quick feel for relative sizes. Compare it with the table in the built-in font list. The wrapped text sample uses a field block, explained in how to wrap text with ^FB. The barcode sample shows a Code 128 code with a caption, and the rotation sample shows how the four orientations behave. If rotated text lands somewhere unexpected, read the section on rotation in the ^A command guide.

Checking sizes and resolution

Choose the DPI that matches your printer and set the default label size in millimetres. The line under the preview tells you the label's size in dots and in millimetres, which is a quick check that you've set things up right. If you're moving a design between printers of different resolution, change the DPI and see how much room there is. Our 203 versus 300 DPI article explains how to rescale.

Sharing and saving

The page accepts ZPL in its address, so a link can carry a label with it. The label generator and the text-to-graphic converter both use this to hand you over for a closer look. The Save PNG button exports what you see, which is handy for documentation or for showing a colleague a layout without a printer in sight.

Questions

Why does my label look different on the printer? Real fonts, real media and real heat. Use the preview for layout and the printer for the final look.

Does it send my ZPL anywhere? No. It runs in your browser.

Can it preview graphics from the converter? Yes, including the compressed form.

What if text is clipped in the preview? That's useful information. See text cut off or wrong size.