QR Codes: The Complete Guide for 2026

What a QR code actually stores

A QR code is a two-dimensional barcode that holds text, usually a URL. The encoder converts the URL into a grid of modules, adds error-correction data and appends the pattern markers a camera uses to orient the image. Because error correction is built in, a code still scans when part of it is dirty, folded or covered by a logo.

Error correction comes in four levels: L (about 7%), M (15%), Q (25%) and H (30%). Level H is what lets you place a logo in the middle of a code, but it also stores more redundancy, which makes the code denser for the same URL. A short URL matters here: the shorter the encoded text, the fewer modules, and the easier the code is to scan from a distance.

Generate the code from a short link, not the raw URL

Encoding https://example.com/campaigns/2026/autumn?ref=poster&utm_source=print produces a dense code with a fixed destination. Encoding tinyto.me/autumn produces a sparse code that you can re-point later. If a campaign URL changes, you update the short link and every printed code keeps working.

Sizing and contrast

• Minimum size: around 2 × 2 cm for a close-range scan, and roughly 1 cm of code width for every 10 cm of scanning distance as a rule of thumb.
• Quiet zone: leave a margin of at least four modules around the code. Text, borders or a busy photo touching the code is the most common cause of failed scans.
• Contrast: dark modules on a light background. Inverted codes work on some phones, not all.
• No gradients across modules: the camera needs hard edges, not a smooth blend.

Where QR codes earn their place

Packaging, restaurant tables, event badges, invoices, shop windows and printed ads are all cases where a typed URL would never be used. For a digital-only audience the code adds little; a normal link is faster.

Measure the scans

A code generated from a TinyTo link records the same data as any other click: total scans, country, device and referrer. That turns print into a channel you can compare with email or social instead of guessing.

Test before you print

Scan the final artwork on the material you will print on, from the distance a real person will use, with both an iPhone and an Android device. Screens hide problems that ink and paper reveal.

Generate a free QR code · Create a memorable short link first · Read the scan data