{{ summaryTitle }}
{{ summaryValue }}

{{ summaryLine }}

Payload{{ resultsReady ? `${computation.values.payload_bytes} B` : '—' }} Version{{ resultsReady ? `V${computation.values.version_estimate}` : '—' }} ECC{{ resultsReady ? computation.normalizedInputs.error_correction : '—' }}
Generate one URL, text, Wi-Fi, email, call, SMS, contact, or calendar-event symbol.
Include https:// and the exact path or query string.
Enter the exact note or instruction to reveal after scanning.
For example, +12025550123.
Choose 160–1400 export pixels, then test the final physical placement.
px
{{ quietZoneModules }} modules
Keep at least four modules unless the final artwork supplies equivalent clear space.
Decorative modules change appearance, not payload text.
Square is the conservative finder-pattern baseline.
A near-black foreground gives the strongest default scan contrast.
FG
White is the conservative background baseline.
BG
Leave off unless the placement surface is controlled.
{{ transparentBackground ? 'On' : 'Off' }}
Leave off for the conservative single-color result.
{{ gradientEnabled ? 'On' : 'Off' }}
None keeps the raw symbol artifact.
Up to 42 characters.
{{ logoScale }}%
The setting applies only when a logo image is attached.

{{ logoDataUrl ? 'Logo attached' : 'Drop one logo image' }}

PNG, JPEG, WebP, or SVG up to 2 MB.

The chart renderer is unavailable. Exact scores remain in the payload ledger and scan review.

FieldValueMeaningCopy
{{ row.label }}{{ row.value }}{{ row.detail }}
CheckStatusCurrent valueNext actionCopy
{{ row.check }}{{ row.status }}{{ row.value }}{{ row.action }}
Quick Response (QR) Code Decoder Decode a QR image locally, inspect the recovered payload, and flag suspicious links or sensitive OTP and Wi-Fi data before opening.
Favicon Generator Turn one logo into a local favicon ZIP with profile-sized PNG and ICO assets plus ready-to-copy HTML links and manifest data.
QR Batch Generator Generate named QR images from pasted rows or CSV/TXT files, then catch capacity and scan-readiness risks before downloading the batch.
Image Resizer Resize one image locally, compare fit or crop geometry, and tune format quality against a file-size target before downloading.

A QR code carries text through a camera. The text may be a web address, Wi-Fi record, contact card, message draft, phone action, or calendar event. Scanning reconstructs that payload; the receiving app decides whether to open a site, join a network, save a contact, or prepare another action.

The square symbol is built from modules, the small light and dark cells arranged around finder patterns and other fixed structures. A longer UTF-8 payload usually needs a higher QR version and more modules per side. When the same symbol is printed at a fixed size, more modules mean each module becomes smaller and harder for a camera to distinguish.

Error correction adds redundant data so some damage can be recovered. Higher levels improve recovery margin but reduce the number of payload bytes available at each version. The quiet zone, a clear border around the full matrix, helps a scanner separate the symbol from nearby artwork. Strong light-dark contrast and an unobstructed matrix remain important even when error correction is high.

Placement Main risk Useful check
Screen or slide Glare, viewing angle, or insufficient on-screen size Scan from the expected distance on more than one phone.
Flyer or menu Printer softness, scaling, or artwork entering the quiet zone Test the final PDF or physical proof at 100% scale.
Poster or sign Modules too small for the viewing distance Test from the farthest realistic scanning position.
Logo overlay Covered data modules and reduced recovery margin Keep the logo modest, raise error correction, and scan the exported artwork.

A code that scans successfully can still be wrong or unsafe. A shortened or mistyped URL may lead elsewhere, a Wi-Fi symbol reveals its stored password to anyone who can inspect it, and a calendar record without a timezone may be interpreted as local time. Verify both the decoded payload and the real action before distribution.

How to Use This Tool:

Define the action first, then prepare the symbol for its final placement rather than judging it only in the browser preview.

  1. Choose the payload type. Enter the complete destination or record fields. Use an absolute HTTP or HTTPS URL, match a Wi-Fi network name exactly, and check contact or event details before styling.
  2. Select the use case and error correction. Screen, print, poster, and logo presets apply different starting values. Higher error correction helps with damage or overlays but can increase density.
  3. Adjust the physical safeguards. Keep at least four quiet-zone modules for ordinary placement, choose a dark foreground on a light background, and use a large enough export canvas for the final physical size.
  4. Review the warnings. Inspect Scan review for capacity, contrast, quiet-zone, logo, background, and error-correction status. Treat Fix as a required change and Review as a reason to test more carefully.
  5. Test the exported symbol. Decode it from the actual file or print, confirm the reconstructed payload, and try the expected action on several devices before publishing it.

Interpreting Results:

The readiness score is a local planning heuristic, not a certification that every scanner will succeed. It combines payload utilization, contrast, quiet zone, logo coverage, and selected error correction. Real print size, viewing distance, camera quality, focus, glare, curvature, and surface damage are outside that score.

Band Score Meaning
Robust 85 to 100 The selected settings leave comparatively strong modeled margin.
Balanced 70 to 84 The symbol has workable modeled settings but still needs final-use testing.
Risky 50 to 69 One or more factors materially reduce modeled scan margin.
Fragile Below 50 Change the flagged settings before relying on the symbol.

The version and module counts are estimates used for planning. The QR symbol remains the artifact to decode. Check the payload ledger for the exact stored string, especially after using Wi-Fi, email, contact, or event fields that require escaping or serialization.

Technical Details:

Payload fields are normalized into one text record, counted as UTF-8 bytes, and matched to a byte-mode capacity table for the chosen error-correction level. The smallest version whose table entry fits the byte count becomes the planning version. Versions run from 1 through 40.

Transformation Core

Payload Serialized form
URL or text The validated text is encoded directly. URLs must be absolute HTTP or HTTPS addresses.
Wi-Fi WIFI:T:security;S:ssid;P:password;H:true;;, with reserved characters escaped and the hidden field omitted when false.
Email A mailto: URI with percent-encoded subject and body query values when present.
Phone or SMS tel:number for calls and SMSTO:number:message for an SMS draft.
Contact A vCard 3.0 record with required full name and optional organization, title, phone, email, and URL fields.
Event An iCalendar 2.0 event. Local date-time inputs are written as floating DTSTART and DTEND values without a timezone identifier.

Formula Core

Once version v is selected, the matrix width and two size estimates follow directly.

M = 17+4v pmodule = pcanvasM pquiet = round(pmodule×q)

M is modules per side, pcanvas is the export size in pixels, and q is the quiet-zone width in modules. Canvas size ranges from 160 through 1,400 pixels. The physical module size still depends on how that image is placed or printed.

Logo coverage uses the square of the logo-width fraction. A logo set to 20% width therefore covers an estimated 4% of the symbol area, before any shape-specific detail is considered.

C = (w100)2 × 100

The overall readiness score is the rounded weighted sum of five component scores, clamped to 0 through 100.

R=round( 0.30Scapacity+ 0.22Scontrast+ 0.18Squiet+ 0.15Slogo+ 0.15Secc )
Component Exact scoring rule
Capacity 100 through 60% utilization; linear decline to 70 at 85%, then to 35 at 100%; above capacity declines by 120 points per excess ratio and stops at 0.
Contrast 100 at 7:1 or higher; linear from 75 at 4.5:1 to 100 at 7:1; below 4.5:1 scales from 0 to 75.
Quiet zone min(100, modules ÷ 4 × 100).
Logo 100 with no logo or up to 10% area; 88 above 10% through 15%; 72 above 15% through 20%; and 55 above 20% through the reachable 20.25% maximum.
Error correction L = 55, M = 72, Q = 86, and H = 100.

Rule Core: Capacity and Status Boundaries

At version 40, the modeled byte capacities are 2,953 bytes for L, 2,331 for M, 1,663 for Q, and 1,273 for H. A larger payload is rejected. Within the selected version, utilization above 85% is Review and above 100% is Fix. Contrast uses the weakest ratio among the foreground and any enabled gradient endpoints against the effective background; transparent output is modeled against white.

  • Contrast below 4.5:1 is Fix; 4.5:1 through less than 7:1 is Review.
  • Fewer than four quiet-zone modules is Fix. Poster use with four or five modules is Review.
  • Logo coverage above 20% is Fix unless error correction is H. Coverage above 15% is otherwise Review.
  • A transparent background is always Review because the final placement supplies the effective background.
  • Error correction L or M outside the screen preset is Review.

Privacy and Safety Notes:

Payload construction and attached-logo handling take place in the current browser session. A logo may be PNG, JPEG, WebP, or SVG up to 2 MB. The finished symbol is not secret: anyone who can scan or decode it can recover its payload.

  • Do not encode a private Wi-Fi password on material that can leave the intended area.
  • For public links, open the exact destination from the decoded payload and check that the domain, path, and query are correct.
  • SMS and email codes prepare drafts; the receiving app controls the final send action.
  • Test floating calendar times in the target calendar because no timezone identifier is included.
  • Keep an accessible printed alternative for people who cannot scan the symbol.

Worked Examples:

Guest Wi-Fi card

A WPA network named Lobby with password samplepass and no hidden-network flag becomes WIFI:T:WPA;S:Lobby;P:samplepass;;. Confirm the decoded network name and password on a device that is not already connected, then place the card where only intended guests can read it.

References: