Guide
Structure, scanning practice, and mistakes to avoid when you generate static codes in the browser.
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.
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.