What this QR code generator does
This tool turns any text or web address into a scannable QR code — with module shapes, a gradient, a frame, separately styled eyes and a center logo. A safety check counts how many modules your logo covers, a scan check reads the finished code back, and you download the result as PNG, SVG or print-ready EPS/PDF — entirely in your browser.
When is a QR code useful?
QR codes turn something digital into something you can point a phone at:
- Link a printed item to the web — a flyer, poster, business card, menu or label.
- Share a Wi-Fi network, address or contact without anyone typing it out.
- Put a payment or booking link on an invoice, sign or packaging.
- Bridge a slide deck or video to a page people can open on their own device.
Because the code is generated on your device, it is just as suitable for an internal intranet URL as for a public campaign.
How does error correction work?
Every QR code carries redundant data so it can still be read when part of it is dirty, crumpled or covered. The four levels and their recovery capacities are defined in the QR standard ISO/IEC 18004 — you choose how much redundancy to include:
| Level | Recovers up to | Good for |
|---|---|---|
| L | 7% | Clean screens, large codes |
| M | 15% | The everyday default |
| Q | 25% | Print that may scuff |
| H | 30% | Small print, or codes with a logo |
When you drop a logo or label into the centre, the generator automatically switches to level H. The denser pattern is the trade-off for that resilience.
How big can the center logo be?
The logo area sits centred and is fixed at just over a fifth of the code's width (22%) in this tool — there is deliberately no slider for it, because much larger logos make codes unreliable. Instead of hoping, the tool does the math: it counts the modules that sit under the logo area and holds that share against the recovery capacity of each level — as a plain statement like “your logo covers 11% of the modules; level M carries that, level L does not”. Two limits of this calculation are stated honestly:
- Area is not capacity. The recovery figures in the standard apply to codewords (groups of 8 modules), not to area — a partially covered codeword is already fully affected. The count is therefore a deliberately conservative approximation, not a proof.
- A covered finder pattern is always fatal. If the logo area reaches into one of the three eyes, the tool warns hard — the scanner then never finds the code in the first place, no matter the error correction level. With this tool's fixed, centred logo area there is always clearance to the eyes — the warning is the built-in safety net in case a code ever leaves that geometry.
The counter-evidence to the calculation is the scan check: it decodes the fully rendered code with the same decoder this site's QR scanner uses. The calculation predicts, the check proves — only when both are green is the code a safe choice. Still do a real test scan before a print run.
What are the eyes — and how far can I style them?
The three large squares in the corners are the finder patterns, or eyes: they are how a scanner detects that a QR code is there and how it is oriented. This tool styles them separately from the rest — outer ring and pupil each take their own shape (square, rounded, circle) and their own color. Ring and pupil are deliberately independent, because the most common design — a rounded ring with a circular pupil — would be impossible with coupled values.
The eyes are function, not decoration: overly soft shapes or weak colors can hinder detection, which is why the eyes get their own contrast warning and the scan check re-runs automatically after every eye change. In the EPS/PDF export the eyes deliberately stay solid squares — styled eyes travel in the SVG and PNG. Before printing, the usual rule applies: do a real test scan.
Colours, gradients and contrast
You can recolour the modules, switch to a two-colour gradient, pick any background or leave the background fully transparent (PNG and SVG keep the transparency). The one rule scanners care about is contrast: dark modules on a light background read most reliably. The tool computes the contrast ratio of your colours live and warns before it gets too weak. On top of that, the scan check reads the generated code back with the same decoder this site's QR scanner uses and tells you whether it really decodes — for a transparent background it is checked on both a light and a dark surface. Both judge the ideal on-screen image, not the eventual print: always do a real test scan before you print a large run.
How large will the print be — and from how far can it be scanned?
For the chosen PNG resolution the tool shows the print size in millimetres, and the math is deliberately transparent: px ÷ dpi × 25.4 (one inch is 25.4 mm). At the usual 300 dpi, 1024 px come out at roughly 86.7 mm per side and 4096 px at roughly 35 cm — the resolution (150/300/600 dpi) is switchable. The calculation uses the real size of the download: the PNG is drawn with whole pixels per module (crisp module edges instead of antialiasing), so the chosen size is rounded down to the nearest multiple of the module count — 512 px can become 495 px for a small code with its quiet zone, and that exact number is what the display shows.
For the scanning distance there is the widespread rule of thumb that the code should be about one tenth as wide as the distance (a 10 cm code carries roughly 1 m). Honestly classified: that is a practice rule without a normative source — neither ISO/IEC 18004 nor Denso Wave's guidance states a distance ratio. Denso Wave, the inventor of the QR code, instead ties readability on qrcode.com to module size and scanner resolution: the larger each module, the more stable the read. Take the rule of thumb as a starting point and test at the real distance.
PNG, SVG, EPS or PDF?
When a print shop asks for a vector file, download EPS or PDF — those are the two formats a prepress department accepts without a follow-up question.
- SVG is vector: it stays perfectly crisp at any size, which makes it the right choice for signage or anything you might resize later. The gradient, the module shape, the styled eyes and an embedded logo all travel inside the file.
- EPS and PDF are the route to the printer. Both are deliberately reduced: one solid colour, square modules, standard eyes, no frame and no centre logo. A gradient falls back to its start colour — so download styled codes as SVG and print-ready ones as EPS or PDF.
- PNG is a pixel image, handy for chats, slides and websites. Pick the resolution that fits — 256 px for small on-screen use, 2048 or 4096 px for posters. Optionally with a transparent background, the PNG keeps its alpha channel.
Your data stays private
The whole code — including any logo you upload — is built locally in your browser. Nothing is uploaded, there is no account and no tracking. The codes are static: they encode your text or URL directly, so there is no redirect in between and they never expire.