Qraft StudioQR • BARCODE • NFC

Frequently Asked Questions

Everything you need to know about matrix resilience, retail barcodes, Web NFC programming, client-side privacy, and commercial vector printing.

General & Privacy

Learn about how the studio works, pricing, and client-side security.

Q.Is Qraft Studio free to use?

Yes! All studio generators (QR Code Studio, Barcode Studio, and NFC Studio) are 100% free with unlimited exports in high-resolution PNG, SVG, and PDF formats. No registration, watermarks, or subscription plans are required.

Q.Are my QR codes and barcode data stored on external servers?

Never. All matrix calculations, barcode rendering, and NFC payload generation happen strictly client-side inside your browser via local JavaScript engines. Your Wi-Fi passwords, contact details, private serial keys, and personal credentials are never uploaded, logged, or tracked on any remote server.

Q.Do generated QR codes expire or have scan limits?

Standard static QR codes generated here never expire and have unlimited lifetime scans. Because your destination URL or credentials are mathematically encoded directly into the 2D binary matrix according to ISO/IEC 18004 standards, the code functions forever without any middleman redirect servers, subscriptions, or paywalls.

Q.Why do some online QR code generators stop working after 14 days?

Many commercial generators quietly default to 'Dynamic QR Codes'. Instead of encoding your actual link, they encode a proprietary redirect URL owned by their company. After a 14-day trial period or 50 scans, they lock the redirect behind a monthly subscription ($15–$40/mo), holding your printed materials hostage. Qraft Studio generates 100% permanent static codes with zero redirect dependencies.

QR Code Creation & Design

Best practices for dot styles, logos, frames, and error correction.

Q.What is Error Correction Level (L, M, Q, H)?

Error correction uses Reed-Solomon mathematical algorithms to restore missing or damaged modules. Low (7%) is optimal for simple digital screens. Medium (15%) is standard for flyers. Quartile (25%) and High (30%) are recommended when embedding center logos or placing codes in harsh outdoor environments.

Q.Can I print a transparent background QR code on dark packaging or bottles?

You must be cautious: smartphone cameras convert images to grayscale optical luminance (Rec. 709). If you print black QR modules directly onto brown kraft cardboard, dark glass, or brushed metal, the contrast ratio drops below 35% and scanners fail. For non-white substrates, packaging printers must lay down a 'White Ink Underprint' base layer with a 0.1 mm choke trap before printing the dark modules.

Q.How do UPI payment QR codes work for merchants and stores?

UPI QR codes follow the National Payments Corporation of India (NPCI) deep-link standard (upi://pay?pa=VPA&pn=Name). Scanning instantly opens payment apps like Google Pay, PhonePe, or Paytm with zero transaction fees. Counter standees with no pre-filled amount allow customers to enter exact totals and verify transactions in real time.

Q.Can I add my company logo to the center of a QR code?

Yes. Our QR Studio allows you to upload custom PNG, SVG, JPG, or WebP logos. The studio automatically enables high error correction (Q or H) to ensure the code remains 100% scannable even with your logo covering the center modules.

Q.What is the minimum recommended print size for a QR code?

For standard close-range scanning on business cards or flyers, the recommended minimum size is 20 mm × 20 mm (0.8 × 0.8 inches). For greater scanning distances, follow the 10:1 ratio (distance divided by 10 equals minimum code width).

Q.How do Wi-Fi and vCard QR codes work?

Wi-Fi QR codes encode the network SSID, security type (WPA/WPA2/WPA3), and password using the standardized WIFI: format. When scanned by an iOS or Android device, it automatically connects to the network without typing. vCard codes encode an electronic business card that imports directly into the user's contacts.

Barcodes & Symbologies

Retail standards, checksum calculations, and industrial shipping formats.

Q.What is the difference between EAN-13 and UPC-A barcodes?

UPC-A is a 12-digit standard primarily used in the United States and Canada, while EAN-13 is a 13-digit standard used across Europe, Asia, and international markets. EAN-13 is a superset of UPC-A; prefixing a leading zero to any UPC-A code makes it fully compliant with EAN-13 scanners.

Q.Why is ITF-14 used on corrugated cardboard instead of EAN-13?

Standard retail barcodes have fine lines that bleed and spread when printed flexographically onto rough, porous corrugated cardboard. ITF-14 (Interleaved 2 of 5) uses wider bars and thick horizontal 'Bearer Bars' that equalize press pressure and prevent short scans, making it the GS1 global standard for outer master shipping cartons.

Q.How is the barcode check digit calculated?

Standard retail barcodes (EAN-13, UPC-A, ITF-14) use a Modulo-10 checksum algorithm. Our studio automatically calculates and validates the check digit in real time as you type, alerting you if an invalid digit is entered.

Q.Can I print barcodes on thermal printers like Zebra, Brother, or Dymo?

Yes. For thermal label printers (203 DPI or 300 DPI), always export your barcodes as mathematical vector SVG or high-resolution PNG (2x/4x scale). Thermal print heads only print pure black or white; vector geometry eliminates gray pixel dithering that causes optical scanner rejections.

Q.Which barcode format should I use for warehouse shipping and inventory?

Code 128 is the industry standard for supply chain logistics, warehouse inventory, and shipping labels. It supports all 128 ASCII characters, including letters, numbers, and punctuation, with high encoding density.

NFC Studio & Smart Tags

NDEF payloads, Web NFC API integration, and hardware compatibility.

Q.What is the difference between NTAG213, NTAG215, and NTAG216 chips?

The primary difference is usable user memory: NTAG213 offers 144 bytes (best for simple URLs under ~132 characters), NTAG215 offers 504 bytes (ideal for vCards and Amiibo), and NTAG216 offers 888 bytes (for complex contact cards with physical addresses and notes).

Q.Why do standard NFC stickers fail when placed on metal surfaces?

Metals like aluminum and steel reflect the 13.56 MHz radio frequency emitted by smartphone NFC antennas, canceling the magnetic field. To attach NFC tags to metal laptops, tumblers, or steel doors, you must use specialized 'On-Metal' (Anti-Metal) NFC tags that include a protective ferrite barrier layer.

Q.What is an NDEF payload?

NDEF (NFC Data Exchange Format) is a lightweight binary messaging format standardized by the NFC Forum. It allows smart tags to store text memos, website URLs, and custom MIME payloads that can be read by NFC-enabled smartphones.

Q.Can I write to an NFC tag directly from my browser?

Yes! On modern Android devices using Google Chrome or Chromium browsers, our NFC Studio integrates with the W3C Web NFC API, allowing you to write formatted NDEF payloads to physical NTAG213, NTAG215, and NTAG216 tags with a single click.

Q.Can iPhones read NFC tags generated here?

Yes. All modern iPhones (iPhone 7 and newer running iOS 13+) natively read standard NDEF URL and Text tags in background scan mode without requiring any third-party app.

Printing & Vector Exports

File formats, resolution scaling, and commercial print preparation.

Q.Should I export in SVG or PNG for professional printing?

Always choose SVG (Scalable Vector Graphics) or PDF for professional commercial printing. Vector files scale to any dimension (from business cards to massive roadside billboards) with crisp mathematical edges and zero pixel blur. PNG is ideal for web pages, social media, and email signatures.

Q.What resolution presets are available?

You can export raster graphics in 512px (web/mobile), 1024px (HD), 2048px (large print), 4096px (ultra vector master), or define custom pixel dimensions tailored to your design software.

Start Generating in Our Studios

Generate QR codes, EAN/UPC barcodes, and NFC tags with zero watermarks, 100% client-side privacy, and high-resolution vector exports.