How big should a QR code be?

Enter a scanning distance and content length to get the minimum print size, with the formula shown.

Your printing scenario

millimeters
characters

Recommended minimum size

100
mm
10
cm
3.94
in

Distance is the limit: at 100 cm away, the code needs to be at least this big to be readable at all, regardless of how simple its pattern is.

Module pattern
29×29 (version 3)
Error correction used
M
Pixels needed at 300 DPI
1182px
Make a QR code at this size

The formula, in full

The calculator above uses a rule of thumb from the print and signage industry, not a number from the ISO/IEC 18004 QR code standard (which does not specify a print size at all). It takes the larger of two limits:

minSizeMm = max(distanceMm / 10, modules × 0.4mm × densityFactor)

The first term is the classic “one-tenth of the scan distance” guideline: a code meant to be read from 1 meter away should be at least 100 mm across. The second term accounts for how much data the code holds. More content forces a higher QR version with more modules packed into the same grid, and each module needs roughly 0.4 mm to resolve cleanly on a phone camera at close range. densityFactor is 1.0 for versions 1–10 and 1.25 for versions above that, since denser codes lose a little more resolving power than the raw module count suggests. Whichever term is larger “wins” and becomes the calculator’s driver sentence.

Common scanning distances

Use caseDistanceDistance-limited minimum
Business card250 mm25 mm
Table tent500 mm50 mm
Poster1000 mm100 mm
Shop window2000 mm200 mm
Billboard10000 mm1000 mm

These are only the distance term; a code with a lot of content or a logo can still be density-limited even at a short scan distance, which is why the calculator computes both terms rather than using a lookup table.

Why logos need bigger prints

Covering the middle of a QR code with a logo removes real data modules. The code compensates with error correction, which can reconstruct missing modules up to a point, but only if enough of the pattern survives. Our calculator forces at least Q-level error correction whenever the logo toggle is on, which raises the module count, and adds a further 15% to the final size to keep the remaining modules large enough to read reliably. If you skip this margin, a branded QR code that tests fine on a phone held six inches away can fail once it’s shrunk onto a business card. Use the design studio’s live scannability score to confirm a specific logo and color combination before you print.

Once you have a size, download the code at the resolution to match: the QR codes for printing page covers vector export and 300 DPI, and the QR code tester lets you verify the exported file decodes correctly before it goes to a printer.

Frequently asked questions

What is the smallest QR code that will scan?

There is no fixed minimum in absolute terms — it depends on the scanning distance and how much data the code holds. A simple, short-URL QR code held a few inches from a phone camera can scan at under half an inch across. The same content printed on a poster meant to be read from across a room needs to be many times larger, because the limiting factor shifts from module density to viewing distance.

Does a longer URL need a bigger QR code?

Yes. More characters force a higher QR version, which packs more modules into the same code, and each module needs a minimum physical size for a phone camera to resolve it cleanly. A short link like quickqrmaker.com/x needs far less size than a long tracking URL with query parameters. Shortening the link or using a service that supports short redirect URLs keeps the printed size down.

Why does adding a logo increase the recommended size?

A logo covers part of the code, so the error correction has to reconstruct more missing data from the modules that remain. We force at least Q-level error correction whenever a logo is present, which increases the module count, and add a further margin so the code stays reliable at the printed size. Skipping this step is the most common reason a branded QR code fails to scan.

Is this calculator based on an official standard?

No. The ISO/IEC 18004 QR code specification does not define a minimum print size; it only defines the code structure and error correction math. The distance-to-size ratio and per-module minimum used here are working rules from the print and signage industry, stated on this page so you can check the arithmetic yourself, not a certified requirement.

What error correction level should I use for print?

M (15% recovery) is a reasonable default for clean printing. Use Q (25%) if you are adding a logo or printing on a textured or curved surface, and H (30%) for harsh environments like outdoor signage exposed to weather and dirt. Higher error correction increases the module count slightly, which this calculator accounts for.