Choose the symbol for the payload and the physical workflow
QR Code & Code 128 Generator Online — Create and Scan Locally
QR and Code 128 are not visual variants of the same barcode. One is a two-dimensional matrix built for flexible payloads; the other is a linear symbol built for fast operational scanning.
QR code
2D matrix · URLs, Wi-Fi, contact data, text
Code 128
1D bars · inventory, shipping, internal identifiers
QR branch
Payload anatomy
Payload → byte encoding → data modules → error correction → mask → finder and timing patterns
Keep a four-module quiet zone and strong contrast
Do not crop the light border, round away module edges, or place a busy image behind the symbol. Higher correction does not repair poor geometry.
Decode before opening
- 1Scan the complete image
- 2Inspect the decoded payload
- 3Check domain and scheme
- 4Open only when expected
Code 128 branch
Symbol anatomy
Module width sets physical reliability
Pixel dimensions are not print dimensions. Choose the final width for printer DPI, viewing distance, scanner optics, and substrate, then preserve the quiet zones.
Human-readable text is a label, not encoded bars
Keep it outside the symbol and never let text, borders, or clipping touch the bars.
A generated symbol is unfinished until it survives a round-trip scan
- 01
Generate with final data
- 02
Render at final physical size
- 03
Scan with multiple devices
- 04
Compare the decoded payload
- 05
Approve the production asset
QR and Code 128 questions
- Does higher QR error correction always scan better?
- No. It adds recovery modules and increases density. Poor contrast, a missing quiet zone, or modules that are too small can still make the code fail.
- Does Code 128 include a checksum?
- Yes. The encoded symbol includes a modulo-103 check character. Human-readable text below it is separate presentation.
- Why test at final print size?
- A large on-screen preview can hide narrow modules, ink spread, scaling interpolation, low contrast, and quiet-zone loss that affect the real label.