FIRST CHTools

FIRST CH TOOLS / Other / 30 QR CODE GENERATOR

QR Code Generator

Type a URL or a message and it becomes a QR code straight away, ready to download as SVG or PNG. The SVG stays sharp at any size, so it can go directly into artwork for business cards, flyers and posters. If the print may get smudged or folded, raise the error correction level. Everything runs on this page — what you type never reaches a server.

Content

The size is the edge length of the PNG you download (the SVG is vector, so this only sets its initial display size). The quiet zone is the white border around the code; the standard recommends 4 modules. Scanners use it to tell where the code ends, so dropping it to 0 can break scanning over a patterned background.

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Version
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Modules
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Error correction
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Capacity used
Result
Type something above and the QR code appears here.

Inside this code
ItemValueWhat it means

Nothing you type leaves the browser — the encoding, the error correction maths and the image export all run on this page. You can also call it straight from a URL: /en/qr/?text=https%3A%2F%2Fexample.com%2F or /en/qr/?text=…&ec=H&size=512&margin=2

How to Use

  1. Enter the contentA URL or plain text — the code is redrawn on every keystroke. For set formats such as Wi-Fi or email, insert a template with the buttons and edit the values.
  2. Pick the size and strengthA higher error correction level survives more damage but makes the code finer. Use Q or H for print, M for screens.
  3. Save itUse SVG for print and design files, PNG for the web and social posts. Once saved, scan it with a real phone before you ship it.

About This Tool

The whole code is assembled on this page.Your text is turned into UTF-8 bytes, prefixed with the mode and character-count bits, extended with Reed–Solomon error correction, laid out around the finder patterns, timing patterns and version information, and finally masked with whichever of the eight patterns scores best. There is no API and no image server behind it, so an internal URL or a client's contact details never leave your machine.

SVG or PNG.An SVG stores shapes rather than pixels, so it stays razor-sharp from business card to poster — use it for print and design files. A PNG is written at the pixel size you choose, which suits web pages, social posts and slide decks. Module edges in the PNG are rounded to whole pixels, so you never get a half-grey seam between modules.

Error correction is how much damage the code survives.A QR code carries spare data so it can be read even when part of it is missing. The four levels run from L (about 7%) to H (about 30%); raising the level makes the code denser for the same content. Choose Q or H for anything printed, exposed outdoors, abraded on a label, or overlaid with a logo. For a code shown on screen, M is plenty — and a coarser code is easier to scan from a distance.

The encoding mode follows your content.Digits alone use numeric mode and uppercase alphanumerics use alphanumeric mode, both of which fit more into the same version. Everything else — lowercase letters, other scripts, most punctuation — goes into UTF-8 byte mode, where a Japanese character costs 3 bytes and fills the code much faster than a URL does. If the content no longer fits, the tool says so (the ceilings are 7,089 digits, 4,296 alphanumeric characters or 2,953 bytes, all at level L).

Keep the quiet zone.Scanners rely on the plain border around a code to find its edges. The standard recommends 4 modules and that is the default here. If layout pressure makes you trim it, at least keep a margin wherever the background is not plain white.

To go the other way and read a code out of an image, use the QR Code Reader. It is useful both for checking that a code you made holds the string you intended, and for inspecting a suspicious code from a flyer or a letter without visiting it (decoded URLs are never opened automatically).

To shrink the images around it, see the WebP converter; to check the print colours, the contrast checker; to add tracking parameters to the link, the URL parameter editor.

Where QR codes go wrong

Shorter URLs scan better

More characters means a higher version, which means smaller modules at the same printed size — so a long URL printed small becomes unreadable. Strip tracking parameters down to the ones you actually need before generating the code.

Wi-Fi strings need escaping

WIFI:T:WPA;S:MyNetwork;P:my-password;;

If the password contains ; : \ , or ", put a \ in front of it. Open networks use T:nopass, and a hidden SSID needs H:true; at the end.

Always test the print, not the screen

Ink spread and paper tint can break a code that scanned perfectly on a monitor. Test at the real size, on the real stock, under the real lighting. As a rule of thumb, modules below 0.4 mm are hard work for a phone camera.

Do not invert or wash out the colours

Scanners expect a dark code on a light background. Inverting it, or using a pale foreground, loses some devices — which is why this tool never produces a white-on-black code. If the design demands colour, keep it genuinely dark and test on real hardware.

A printed code cannot be edited

Once a code is on paper, the URL inside it is fixed. If the destination might change, point the code at a redirect you control so you can change where it lands later.

From AI Agents

The same generator is available as the qr_generate tool on the MCP (Model Context Protocol) server @first-ch/tools-mcp, so an AI agent can call it without a browser and write the SVG straight to a file. See Using these tools from AI agents for setup details.

Install

claude mcp add firstch-tools -- npx -y @first-ch/tools-mcp

Examples

# Turn a URL into an SVG QR code
qr_generate(text="https://tools.first-ch.com/qr/")

# Print-ready: stronger error correction, written to a file
qr_generate(text="https://example.com/", ecLevel="H", size=1024, outputPath="/tmp/qr.svg")

# No quiet zone, plain-text art (readable in a terminal log)
qr_generate(text="WIFI:T:WPA;S:office;P:secret;;", margin=0, format="text")

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