Free · No signup · Works offline

See your print design
at true physical size

Calibrate your screen once, then preview any file — label, card, flyer, package — at its exact real-world dimensions. Catch readability issues before they hit the printer.

Open Tool View on GitHub
print-calibration-tool / app.html
Calibration
px / mm 3.78
Area 1
Width 85 mm
Height 54 mm
Print Setup
Format A4
Scale 100%
85 × 54 mm · 1:1 scale
1:1 Physical Scale

Three steps to true-scale preview

No special hardware, no plugins, no installation — just your browser and something to measure with.

01

Calibrate your screen

Hold a physical 100 mm ruler — or a standard credit card (85.6 × 54 mm) — against your screen. Drag the on-screen ruler until it matches. Your personal px / mm ratio is saved locally for next time.

02

Enter the print dimensions

Type in the exact width and height in millimetres. The tool instantly draws a preview rectangle at precisely that physical size on your screen — what you see is what will print.

03

Load your file & inspect

Drop in your artwork, label PDF export, or screenshot. Zoom, pan, and compare two areas side-by-side. Is that 6 pt footnote actually readable? You'll know before spending a single sheet of paper.

Everything you need,
nothing you don't

Built for designers, packaging engineers, and anyone who needs to be sure before committing to a print run.

True 1:1 Physical Preview

The screen element matches real-world mm exactly after calibration — not an approximation.

Side-by-side Comparison

Define two areas at once — compare a current label version against a revised one in the same view.

Image & Design Import

Load any image file — PNG, JPEG, exported PDF page — with Contain, Cover, or exact-mm placement modes plus drag-to-reposition.

Print at Exact Size

Hit Print — the layout switches to absolute CSS mm units. At 100% scale in your print dialog, output matches your spec exactly.

mm Grid Overlay

Toggle a precise millimetre grid over your artwork to spot alignment issues and measure margins at a glance.

Calibration Memory

Your px/mm ratio is persisted in localStorage — calibrate once per device, use the tool forever without repeating the step.

Who is this for?

Anyone who designs things that get physically printed — and wants to be confident before pressing "send to print."

🏷️

Product Labels & Packaging

Check that ingredients text is legible and logo proportions look right on the actual label size — before ordering thousands of units.

💳

Business Cards & ID Cards

Standard credit-card size is 85.6 × 54 mm. Preview your design at that exact size and catch crowding or font issues instantly.

📄

Flyers & DIN Formats

From DIN A6 postcards to A3 posters — set the dimensions, load your file, and see it life-size on screen.

📦

Box & Packaging Dielines

Verify that fold lines, cutouts, and text panels all have the correct real-world proportions before sending files to the printer.

🔖

Stickers & Hang Tags

Small formats are notoriously tricky on screen. Proof at 1:1 and make font-size decisions with confidence.

🖨️

Last-minute Print QA

Have a deadline and no time for a test print? Use the tool as a rapid sanity check to catch obvious errors in seconds.

100% private by design

Your files never leave your device. Everything runs entirely in the browser — no server, no upload, no account. Images are read as local data URLs and discarded when you close the tab.

No file uploads No tracking No login Works offline

Ready to see it life-size?

Open the tool, calibrate your screen in under a minute, and never waste a test print again.

Open Tool — it's free Star on GitHub