QR Code Size Calculator

Apply the 1:10 rule: the minimum QR size equals the expected scan distance divided by ten. At a 10-inch reading distance, minimum QR is 1 inch; at a 10-foot standing distance, minimum is 12 inches. Add a 20% safety margin for real-world conditions. Our calculator handles this math automatically, adjusted for error correction level, logo overlay, outdoor use, and low-light scanning.

The 1:10 rule states that a QR code must be at least 1/10th the size of the intended scanning distance to reliably scan. It comes from decades of barcode-industry practice and is cited by Denso Wave (QR's inventor) and the ISO/IEC 18004 specification. A QR scanned from 30 inches needs a 3-inch minimum; a billboard scanned from 30 feet needs a 36-inch minimum.

0.8 to 1.0 inches square on a standard 3.5×2-inch card. Reading distance is typically 6-10 inches, giving a minimum of 0.6-1 inch per the 1:10 rule. Use H-level error correction (30% damage recovery) if adding a logo, and leave a 4-module quiet zone around all sides. See our business cards material guide for the full setup.

On a standard 8.5×11 flyer, use 1.5 × 1.5 inches minimum (12-14 inch reading distance). For a wall poster at 3-5 feet, go 3 × 3 inches. For a trade-show backdrop at 10 feet, scale to 12 × 12 inches. Our calculator's poster preset fills this automatically — adjust the distance to match your actual context.

Depends entirely on the highway viewing distance. At 50 feet (close highway exit signage), minimum is 5 feet. At 500 feet (highway billboard), minimum is 50 feet — which is usually impractical, which is why billboard QRs should be scanned while parked, not while driving. Most billboard QRs target 30-100 foot viewing distance, meaning 3-10 foot minimum QR size. Pair with short-URL dynamic QRs to keep the module count low.

Yes, slightly. Higher error correction (Q, H) adds redundant data modules that take grid space — so for the same data payload, Q adds ~5% size and H adds ~10% size. Our calculator applies these modifiers automatically. The trade-off is worth it: H-level survives 30% damage vs L-level's 7%, which is critical for outdoor or wear-prone prints and mandatory when adding a logo.

Depends on scan distance. Close reading (under 12 inches): 300 DPI minimum. Standing distance (1-4 feet): 200 DPI. Drive-by (4-8 feet): 150 DPI. Billboard (20+ feet): 96 DPI is fine because viewing distance hides pixel imperfection. Always export as SVG when possible — vector scales perfectly regardless of target DPI.

The quiet zone is the empty margin around a QR code that scanners need to detect the code's boundary. ISO/IEC 18004 specifies a minimum of 4 modules (the small squares that make up the QR pattern) on all four sides. Without sufficient quiet zone, scanners fail to locate the QR even if the pattern itself is perfect. Our calculator gives you the quiet zone in inches based on your expected module count.

Adding a center logo replaces some of the QR's data modules. At H-level error correction, you can safely cover up to 20-25% of the QR's area with a logo, but you should increase the QR's overall size by 15% to preserve scan reliability. Our calculator applies this modifier when you enable the logo checkbox. For detailed logo rules, see our QR logo tutorial.

Yes, about 15% larger than the 1:10 rule suggests. Outdoor conditions add UV fading (matte the QR to resist), glare from direct sun (scanners struggle with reflective surfaces), and weather wear (micro-scratches eat into error correction). Our calculator bumps sizing by 15% when you check the outdoor box, and recommends H-level error correction for outdoor print.

Roughly 0.4 × 0.4 inches (1 cm square) for a URL QR at close reading distance (6 inches) under good lighting. Below that, scan failure rates climb sharply because phone cameras can't resolve the modules. The practical floor for production use is about 0.8 × 0.8 inches on paper. Smaller is possible on screens at high DPI but rarely used in print.

Practically, no — larger QRs always scan better than smaller ones at a given distance. The only downside is layout: an oversized QR dominates the design and wastes space. Aim for 20-30% above the calculated minimum, not 200%. If space permits, larger is always fine for scan reliability.

Square. QR codes are technically square by specification — their data modules are arranged in a square grid. Any "rectangular QR code" you see is either a different barcode format (like Data Matrix or Aztec) or a square QR with extra decoration. Non-square QRs either don't work or require special scanners.

Run a 20-scan pilot: print 3-5 proof copies at the exact final size and substrate. Scan with an iPhone, an Android, and an older phone. Test at the actual expected distance, in the actual expected lighting (bright outdoor, dim indoor, fluorescent office). Target 95%+ first-attempt scan success. If any single test scenario fails repeatedly, increase the QR size by 20% and retest.