Code Studio / 01
Create a QR code for a link, message, Wi-Fi network, or contact. Customize the design and download a scannable image.
Content type
Encode an absolute website address. Scanning a URL code does not send visitors through greneshadees.com and does not track scans.
https://example.com is an editable example. The preview is generated from this value until you change it.
This entry looks like a host name without http:// or https://.
Encode plain text, including English characters, numbers, punctuation, spaces, line breaks, and Unicode. Line breaks are preserved. Content is not truncated silently.
Build a mailto URI. Compatible devices may open an email application. Scanning does not send an email from this website, and empty subject or body fields are allowed.
Compatible devices may offer to open the phone dialer after scanning. Scanning does not automatically place a call. Country codes are not assumed.
SMS URI support varies by operating system and scanning application. This website does not send messages, and scanning does not automatically send an SMS.
Wi-Fi QR codes store network credentials in readable form. Anyone who scans or decodes the code may be able to read those details. QR encoding is not encryption and does not protect the password.
Creates a vCard 3.0 payload. Contact import behavior depends on the scanning device and application. Optional empty fields are omitted.
Sufficient contrast improves scan reliability. A particular contrast ratio does not guarantee scanning. Avoid light-on-light combinations, transparent backgrounds, busy photographs behind the code, and untested inverted colors.
The selected export size includes the quiet zone. Modules are drawn with integer pixel sizes. If the chosen pixel count is not a multiple of the matrix plus quiet zone, leftover pixels become extra background padding so module edges stay sharp.
The quiet zone is a light margin of at least four modules. It cannot be removed. Preview, PNG, SVG, and print output all keep it.
Higher levels recover from more damage or obstruction, but they reduce payload capacity or enlarge the matrix. A higher level does not guarantee a successful scan, and a damaged code is not always readable.
Selected level: M · — · —
Printer scaling can change the final size. Use actual-size or 100% scaling when the dialog offers it. Results vary by printer, paper, and device camera. A QR code will not scan from every distance.
Enter valid content to generate a QR code.
Zoom changes only the on-screen preview. It does not change encoded content, QR version, export size, error correction, or the quiet zone.
Encoded content
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Character count (UTF-8 bytes): 0
Guidance / 09
These notes improve the odds of a clean scan. They do not promise universal compatibility with every camera or application.
01
Dark modules on a light, even field are easier for cameras to separate.
Example: A charcoal code on cream card stock in even indoor light.
Common mistake: Printing navy ink on dark recycled board.
Corrective action: Choose a light background and confirm the pair still looks distinct in the intended lighting.
02
Scanners use the empty margin to find the code boundary.
Example: A 1024-pixel PNG that still shows four light modules around the matrix.
Common mistake: Cropping the PNG until the finder squares touch the artwork edge.
Corrective action: Keep the default quiet zone in preview, export, and print.
03
Tiny modules blend together on office printers and phone cameras.
Example: A 70 mm card for a handout, tested at arm’s length.
Common mistake: A 12 mm mark on a crowded flyer.
Corrective action: Print at a size you can still see as a grid, then scan a proof.
04
A live scan is the only practical check for that printer, paper, and payload.
Example: Scan a proof copy with more than one phone.
Common mistake: Sending a file that was never opened on a device.
Corrective action: Generate, print a single proof, and scan it before a large run.
05
Warped bottles, deep folds, and glossy curves distort module geometry.
Example: A flat card placed on a table.
Common mistake: Wrapping the code around a narrow cylinder without testing.
Corrective action: Place the code on a flat panel or test the curved surface first.
06
Logos, rounded dots, and photo backgrounds can destroy finder patterns.
Example: A plain high-contrast square with an intact quiet zone.
Common mistake: Dropping a logo into the center without checking version and error correction.
Corrective action: Leave the matrix unmodified. Add labels outside the quiet zone.
07
Medium is a practical default. Higher levels cost capacity.
Example: Level M for a short URL on a clean label.
Common mistake: Level L on a code that will be taped, folded, or partly covered.
Corrective action: Raise the level if the print may scuff, or shorten the payload instead.
08
Shorter payloads produce smaller versions with larger modules at the same print size.
Example: https://example.com/map instead of a paragraph of directions.
Common mistake: Pasting a full formatted letter into a text QR code.
Corrective action: Link to a page, or cut optional vCard fields you do not need.
Types / 10
A URL code stores a website address as text inside the matrix. A compatible scanner can offer to open that address in a browser.
Use case: a poster that should open a public events page.
Example payload: https://example.com/events
This is a static code. It does not hide a redirect and does not collect scan counts. Destination safety is not verified here.
Plain text is stored directly. The scanner typically shows the characters rather than launching a special application.
Use case: a short notice on a workshop door.
Example payload: Workshop opens at 09:00.
Line breaks and Unicode are preserved. Very long notes may need a lower error-correction level or a shorter message.
Email codes use a mailto URI with an optional subject and body. Parameters are percent-encoded.
Use case: a handout that drafts a question to a public inbox.
Example: mailto:[email protected]?subject=Hello
Scanning does not send mail. Behavior depends on whether an email application is installed.
Telephone URIs use the tel: scheme. Visual separators are removed before encoding.
Use case: a desk card that offers a published number.
Example: tel:+12025550123
Compatible devices may open the dialer. Scanning does not place a call, and no country code is invented.
SMS URIs may open a messaging app with a number and optional draft body.
Use case: a field sign that starts a short status text.
Example: sms:+12025550123?body=Hello
Support varies widely by OS and scanner. This site never sends the message.
Wi-Fi payloads follow the WIFI:T:...;S:...;P:...;; convention, including escaped special characters and optional hidden-network flags.
Use case: a guest-network card on a studio table.
Example: WIFI:T:WPA;S:PrintLab;P:sample-pass-only;;
The password stays in this browser. Encoding is not encryption. Anyone who reads the code can recover the credentials.
Contact codes store vCard 3.0 text, including CRLF line endings and escaped commas or semicolons.
Use case: a conference badge that offers a name and optional email.
Example: BEGIN:VCARD / VERSION:3.0 / FN:Jordan Lee / END:VCARD
Import screens differ by device. Empty optional fields are omitted rather than filled with invented details.
Examples / 11
Each row loads fictional sample data into the generator above. Operator contact details are not used as sample payloads.
Reference / 12
01
A QR code is a square grid of dark and light modules. The encoder places data, error-correction, and function patterns into those modules. Decorative squares that ignore this structure are not QR codes.
Example: version 1 uses a 21 × 21 module grid before the quiet zone.
Misunderstanding: any black-and-white mosaic will scan. Cameras look for specific finder geometry and timing rules.
02
Three nested squares in the corners help a scanner locate and orient the code. Matrix & Mark draws these from the Model 2 layout rather than as decoration.
Example: the top-left, top-right, and bottom-left 7 × 7 finders on every version.
Misunderstanding: rounding those corners for style is harmless. Distorted finders are a common reason scans fail.
03
Larger versions add smaller nested squares so cameras can correct distortion across the matrix.
Example: version 2 adds one alignment pattern near the lower right.
Misunderstanding: alignment marks are optional artwork. They are required by the version layout.
04
Versions 1 through 40 increase the matrix from 21 to 177 modules on a side. This studio selects a version automatically from payload length and error-correction level.
Example: a short HTTPS URL often fits version 2 or 3 at level M.
Misunderstanding: a higher version is always better. Extra modules make printed cells smaller at a fixed physical size.
05
Reed–Solomon blocks allow a scanner to recover from missing or dirty modules. Levels L, M, Q, and H increase recovery at the cost of capacity.
Example: switching a long note from H to M can make an oversized payload fit.
Misunderstanding: high error correction means a torn label always scans. Recovery has limits.
06
A light margin of at least four modules surrounds the matrix. Export size includes this margin rather than cropping it to enlarge modules.
Example: a 1024-pixel PNG still contains the four-module border in the background color.
Misunderstanding: trimming that border makes a “bigger” code. It often makes the code harder to find.
07
A static QR code stores the payload in the matrix. After you download the image, the encoded text does not change unless you generate a new code.
Example: a URL code contains https://example.com, not a tracking redirect.
Misunderstanding: static codes report who scanned them. They do not. Scan analytics require a separate redirect service, which this site does not provide.
08
Capacity depends on version, error correction, and encoding mode. This studio uses byte mode with UTF-8 text, which handles mixed scripts at a cost of more bits than numeric mode.
Example: version 1-M holds 14 byte-mode characters after overhead.
Misunderstanding: QR codes encrypt their contents. Encoding is not encryption; anyone can decode the payload.
Proofing / 13
01
Incorrect approach: Modules merge on paper and in camera noise.
Why it can fail: Cameras cannot tell dark cells from light cells.
Better approach: Print large enough that the grid remains visible, then scan a proof.
Practical example: A 70 mm card instead of a stamp-sized mark on a dense flyer.
02
Incorrect approach: The scanner cannot lock onto the square boundary.
Why it can fail: Nearby text or photos are treated as part of the matrix.
Better approach: Keep at least four light modules around every export.
Practical example: Leaving the default quiet zone in a PNG downloaded at 1024 pixels.
03
Incorrect approach: The camera histogram has little difference to work with.
Why it can fail: Pale gray on cream may look stylish and still fail outdoors.
Better approach: Use a dark foreground on a light, even background and read the on-page contrast warning.
Practical example: Classic dark ink on white paper rather than sand on beige.
04
Incorrect approach: The code is scannable but opens the wrong place, or nothing useful.
Why it can fail: A missing scheme or a typo is stored permanently in a static code.
Better approach: Paste the live address, require http(s), and scan before printing.
Practical example: Encoding https://example.com/hours instead of a bare example.com string.
05
Incorrect approach: The version grows, modules shrink, and print quality drops.
Why it can fail: A full letter pasted into text mode may exceed capacity at level H.
Better approach: Shorten the payload or lower error correction instead of truncating in secret.
Practical example: Linking to a page rather than encoding the whole page body.
06
Incorrect approach: The matrix decodes, but the OS ignores tel, sms, WIFI, or vCard.
Why it can fail: An older scanner may show raw text instead of opening Wi-Fi settings.
Better approach: Explain expected behavior and offer a fallback, such as printed SSID text.
Practical example: Testing a Wi-Fi code on more than one phone model.
07
Incorrect approach: The password is visible to anyone who can see or photograph the code.
Why it can fail: A hallway poster becomes a public key ring.
Better approach: Use a guest network and treat the QR code as a readable copy of the password.
Practical example: A table tent for a dedicated guest SSID, not the office backbone.
08
Incorrect approach: Screen previews hide printer gain, gloss, and scale errors.
Why it can fail: A perfect SVG can still fail after a 90% shrink-to-fit print.
Better approach: Scan the actual paper with more than one device.
Practical example: One proof sheet at 100% scale before a bulk run.
Reading / 14
How to Create a QR Code Online — from payload choice through PNG, SVG, and a test scan.
How to Make a QR Code for Wi-Fi — SSIDs, security types, escaping, and password privacy.
PNG vs SVG QR Codes: Which Format Should You Use? — raster and vector export choices.
How to Print a QR Code That Scans Reliably — size, paper, and proofing.
QR Codes for Links, Email, SMS, and Contacts Explained — seven payload types in practice.
Studio / 15
Matrix & Mark is a browser-based studio for static QR codes. Generation runs on this device. There are no accounts, download caps, or scan-tracking redirects.
Hillary Pepper
13 Merrell Ave
Rome, GA 30161
