The complete guide to QR codes
Everything that matters about QR codes, in one place. What the pattern actually encodes, which format to use for each job, how to size and color a code so it scans every time, and where the real risks are. Built to be read by people who want the facts, not a sales pitch.
Start here
A QR code is a two-dimensional barcode that stores text — most often a web address, but it can just as easily hold Wi-Fi credentials, a phone number, or a complete contact card. A phone camera reads the pattern, decodes the text, and acts on it. That is the whole idea. The complexity lives in two questions: what text do you encode, and how do you make the printed result reliable. This guide answers both.
If you just want to make one, the QR code generator on the home page handles every format described below and exports print-ready PNG and SVG. If you want to understand what you are making, read on.
A QR code is only useful if it scans. Contrast, quiet zone, and size do more for reliability than any visual flourish. When in doubt, keep dark dots on a light background with a clear margin.
Choose a format by what you're encoding
Each use case maps to a specific text payload. Pick the one that matches your goal — the linked guide explains the exact format, when to use it, the common mistakes, and deep-links into the generator preset.
Web & content
- QR code for a website link — the default. Point a code at any URL.
- QR code for a PDF — link a menu, manual, or brochure that lives as a file.
- QR code for an app download — route to the App Store or Google Play.
- QR code for a Google Maps location — drop people at an address or pin.
Contact & messaging
- vCard contact QR code — a saveable digital business card.
- Email QR code — open a pre-addressed message with the
mailto:format. - Phone & SMS QR codes — dial a number or pre-fill a text with
tel:andSMSTO:. - WhatsApp QR code — start a chat with a pre-filled message.
Network & social
- Wi-Fi QR code — let guests join without typing the password.
- Instagram QR code — link straight to a profile.
- Google review QR code — send customers to your review form.
Business & events
- Restaurant menu QR code — a contactless menu that loads instantly.
- Event QR code — share tickets, schedules, or a calendar invite.
- Payment QR code — accept payments via your provider's link.
How QR codes actually work
Understanding the anatomy of a code makes every practical decision easier — why a code gets denser as you add data, why error correction costs space, and why some color choices fail. These references go deep without the jargon.
- What is a QR code — the plain-English definition and a short history of why it exists.
- How QR codes work — finder patterns, alignment and timing patterns, data modules, and masking.
- Error correction levels — what L, M, Q, and H (7%, 15%, 25%, 30%) really trade off.
- Static vs dynamic QR codes — the single most important decision before you print.
- QR code vs barcode — why 2D codes hold so much more than a 1D stripe.
- The history of QR codes — from Denso Wave's factory floors to your phone camera.
- Can QR codes expire — the honest answer for static and dynamic codes.
Print, size, and design
A code that looks perfect on screen can fail on a poster or a curved bottle. These guides cover the physical reality of QR codes — resolution, scan distance, file formats, and how far you can push the styling before scanners give up.
- Sizes and print resolution — the scan-distance rule and minimum dimensions.
- Design best practices — color, logos, contrast, and quiet zone.
- PNG vs SVG — which export format to use, and when.
- How to scan a QR code — iPhone, Android, and no-app methods.
Safety and decisions
QR codes are neutral pointers, but the destination can be anything — which is exactly what scammers exploit. And not every job needs a paid platform. Read these before you trust a code or pay for one.
- Are QR codes safe — quishing, malicious redirects, and how to scan defensively.
- Free vs paid QR generators — what you actually pay for, and when it's worth it.
Ready to make one?
Build a static QR code for any format above — fully in your browser, no account, exported as crisp PNG or vector SVG.
Open the generatorFrequently asked questions
Are all QR codes the same?
The square Model 2 QR code is the universal standard that phone cameras read. Variants exist — Micro QR for tiny labels and rMQR for narrow spaces — but for nearly every consumer use you want a standard QR code, which is what this site generates. See what is a QR code for the details.
Do I need an app to scan a QR code?
No. The built-in camera app on every modern iPhone and Android phone scans QR codes natively — point the camera and tap the link that appears. Full instructions are in how to scan a QR code.
Will a QR code I print today still work in ten years?
A static QR code will. The destination is encoded in the pattern itself with no server in between, so it cannot expire. A dynamic code routes through a provider's redirect and stops working if that subscription lapses — see static vs dynamic.
What size should a printed QR code be?
Follow the 10:1 rule: the scan distance should be no more than about ten times the code's width. A 3 cm code scans comfortably from ~30 cm; a poster read from 3 m needs a code around 30 cm wide. Details in sizes and print resolution.