Choose the Correct Code Type

QR Code vs Data Matrix vs Barcode vs Serial Number

Engraving QR Codes on Metal

QR Codes are useful when a metal tag needs to connect a physical item to digital information.

Common QR Code destinations

• Product webpage
• Instruction manual
• Warranty-registration page
• Maintenance record
• Equipment service form
• Contact card
• Restaurant menu
• Wi-Fi information
• Event-registration page
• Asset-management portal

Use the shortest practical data

A short, well-managed URL normally creates a less dense code than a long address containing many folders, parameters and tracking strings.

Keep the QR Code square

Do not stretch the code horizontally or vertically. Distortion changes the module geometry and can reduce readability.

Do not redraw the finder patterns

The large corner patterns form part of the QR Code structure. Avoid decorative modification unless the code has been generated and validated using a suitable specialised workflow.

Engraving Data Matrix Codes on Metal

Data Matrix is commonly selected when a compact 2D code is needed for manufacturing, equipment, electronics, tools or component traceability.

Common information

• Part number
• Serial number
• Batch or lot number
• Production date
• Supplier identifier
• Maintenance reference
• GS1 Application Identifier data where required

Finder-pattern integrity is essential

The solid L-shaped border and alternating clock-track sides must remain clear and correctly formed.

Do not assume ordinary Data Matrix and GS1 DataMatrix are interchangeable

A GS1 DataMatrix includes a defined data structure and control characters. The customer should provide the applicable standard, Application Identifiers and final encoded data.

Engraving Linear Barcodes on Metal

Linear barcodes use bars and spaces arranged horizontally. Common formats include Code 128, Code 39, EAN and UPC, but the correct format depends on the customer’s system.

Linear barcodes require:

• Correct symbology
• Adequate bar width
• Sufficient bar height
• Clear left and right quiet zones
• Strong contrast
• No horizontal distortion
• Suitable scanner orientation

Metal glare can affect reading

A reflective surface can make dark and light regions difficult for the scanner to separate. A matt finish or controlled black marking may improve consistency.

Do not substitute a different format

Code 39, Code 128, EAN, UPC and other barcode formats have different data and formatting rules. Confirm the required symbology before artwork preparation.

Engraving Serial Numbers on Metal

Serial numbers provide a unique human-readable identity for each item.

A good serial-number format should be:

• Unique
• Consistent in length
• Easy to read
• Easy to sort
• Compatible with the customer’s database
• Free from ambiguous characters where possible

Illustrative formats

Preserve leading zeros

Spreadsheet software may convert 000123 into 123 unless the column is formatted as text. This can break fixed-length numbering and create mismatches.

Avoid confusing characters

Depending on the workflow, consider avoiding combinations such as O and 0, I and 1, or S and 5.

Decide What Data Should Be Encoded

The machine-readable code should contain the minimum data required by the business process.

Possible QR Code data

• Short URL
• Asset-record URL
• Product-support page
• Contact details
• Plain text reference

Possible Data Matrix or barcode data

• Part number
• Serial number
• Lot number
• Production date
• Database key
• GS1-formatted data where applicable

Do not encode unnecessary personal information

A visible code can be photographed or copied. Use a secure database reference rather than placing confidential information directly inside the symbol.

Static Data vs Managed Links

Static QR Code

The destination is encoded directly into the symbol. Changing the destination normally requires generating and engraving a new code.

Managed redirect or database link

The code can point to a controlled short URL or record identifier. The destination content may then be updated without changing the physical code, subject to the customer’s system.

Long-term considerations

• Domain ownership
• Hosting continuity
• Redirect maintenance
• Access permissions
• Data backup
• Privacy policy
• Link-expiry risk

Security and Privacy

An ordinary QR Code, Data Matrix or barcode is a data carrier. It should not be treated as secure merely because the data is represented graphically.

Safer practices

• Encode a database reference instead of confidential data
• Require authentication for sensitive records
• Use access-control permissions
• Avoid exposing customer names or private identifiers unnecessarily
• Use HTTPS for web links
• Maintain a process for disabling lost or stolen asset links
• Review personal-data obligations before publishing information

Codes can be copied

Laser engraving makes the physical mark difficult to alter casually, but it does not prevent someone from photographing or reproducing the encoded data.

Data Density and Physical Code Size

Every QR or Data Matrix symbol is made from small square cells or modules.

More data normally means:

• More modules
• A denser code
• Smaller cells at the same physical size
• Higher sensitivity to blur, glare and engraving spread
• A greater need for controlled verification

Ways to reduce density

• Use a shorter URL
• Encode a database identifier instead of the full record
• Remove unnecessary text
• Select a suitable error-correction level
• Use the code type specified for the application

Module or Cell Size

Module size is the physical width and height of one square element in a two-dimensional code.

Module size must match the process

If the modules are too small, laser spot size, heat, material reaction, focus error or surface texture may cause neighbouring cells to merge.

No single minimum size fits every job

Practical module size depends on the laser, lens, metal, surface finish, marking process, reader, lighting and applicable standard.

Test at final production size

A large sample that scans successfully does not prove that a smaller final version will work.

Protect the Quiet Zone

A quiet zone is the clear area surrounding a machine-readable symbol.

QR Code

A standard QR Code requires a clear margin four modules wide on every side.

Data Matrix and linear barcodes

Follow the quiet-zone requirement of the applicable symbology and customer standard. Do not assume that every code type uses the same margin.

Keep the quiet zone free from:

• Text
• Decorative borders
• Logos
• Holes
• Screws
• Cut edges
• Welds
• Strong surface scratches
• Colour changes
• Other engraved graphics

QR Code Error-Correction Levels

QR Codes support several error-correction levels. Higher error correction can help restore data when part of the code is damaged or obscured, but it also increases the amount of symbol data.

Higher error correction may be useful when:

• The tag may become dirty
• Minor scratches are expected
• The environment is industrial
• The code may experience partial obstruction

Higher is not automatically better

At a fixed physical size, a higher correction level can create smaller modules and a denser code. The level should balance the environment, data length and available area.

Error correction is not permission to damage the symbol

Do not place logos, holes or text over the code merely because error correction is enabled.

Contrast, Lighting and Metal Reflectivity

A scanner must distinguish light cells from dark cells.

Possible high-contrast combinations

• Black marking on matt stainless steel
• Bright marking on black anodised aluminium
• Dark marking on light coated metal
• Paint-filled deep engraving with controlled background contrast

Reflective metal can be difficult

Mirror stainless steel, polished aluminium and curved products can produce glare, hotspots or dark reflections that change with the scanning angle.

Negative or reversed contrast

Some readers and specifications support light symbols on dark backgrounds. Confirm compatibility with the intended scanner and applicable standard.

Test the actual lighting

A code that scans under studio lighting may behave differently under factory lights, sunlight, shadows or mobile-phone flash.

Select the Suitable Metal-Marking Process

Black or dark marking

Suitable for detailed QR, Data Matrix and serial-number marks when high contrast and minimal depth are preferred.

Coating removal

Suitable for anodised, painted or powder-coated metal where removing or changing the coating produces contrast.

Light or frosted marking

May be suitable on dark or reflective materials, but readability depends strongly on lighting and viewing angle.

Deep engraving

Suitable when a physical recess is required, but small cells and narrow bars can become distorted if the depth is excessive.

Review Black Marking vs Deep Engraving on Stainless Steel for a detailed process comparison.

Black Marking vs Deep Engraving for Codes

Choose according to lifecycle

A compact QR code on a premium card may favour black marking. A Data Matrix code on a part that will later be painted or blasted may require an appropriately engineered recessed process.

Metal and Surface-Finish Considerations

Read Laser Engraving on Metal: What Customers Need to Know Before Ordering before selecting the metal.

Position, Orientation and Safe Margins

Place the code on a stable area

Avoid seams, welds, holes, deep scratches, sharp curves, textured zones and areas likely to be covered by mounting hardware.

Keep a safe distance from edges

Cutting tolerances, rounded corners and physical handling can damage modules placed too close to the product edge.

Consider normal scanning orientation

QR and Data Matrix symbols can support orientation detection, but the product should still be positioned for convenient access and suitable lighting.

Avoid areas exposed to constant abrasion

Handles, gripping surfaces, sliding areas and contact points may experience faster wear.

Curved and Cylindrical Metal Products

Codes engraved on bottles, tumblers, tubes and curved equipment can be distorted by surface curvature.

Main risks

• Part of the code moves outside the focal range
• Modules appear wider near the curve
• Reflections change across the surface
• The scanner cannot view the entire symbol at once
• Rotary positioning introduces alignment error

Reduce the width

A smaller code may remain within a flatter section of the cylinder, but the modules must still remain large enough to engrave and scan.

Provide product dimensions

• Diameter
• Circumference
• Taper
• Engraving height
• Seam position
• Handle position

Artwork Preparation

Generate the code from final approved data

Do not use a screenshot copied from a document or messaging application when the original code can be generated directly.

Preserve square geometry

All modules should remain aligned to a consistent grid. Avoid image resampling that creates blurred or partially grey edges.

Keep the source data

Store the text, URL, serial number or GS1 data used to generate every code.

Separate graphic layers

• Code
• Human-readable serial number
• Company logo
• Border or cut line
• Mounting holes

Review How to Prepare Vector Artwork for xTool Creative Space for general vector-file preparation.

Vector vs Bitmap Codes

Do not apply artistic tracing

Automatic image tracing can round corners, alter module size and create unnecessary nodes. Generate a clean code directly whenever possible.

Prepare the Variable-Data Spreadsheet Carefully

A spreadsheet should act as the approved source of truth for batch production.

Recommended columns

Data-cleaning checks

• Remove accidental spaces
• Confirm capitalisation
• Preserve leading zeros
• Check for duplicates
• Check for missing records
• Confirm link destinations
• Lock the approved version

Automatic Serial Numbering

Automated numbering can reduce manual artwork preparation, but the numbering rules must be approved before generation.

Define:

• Starting number
• Ending number
• Number of digits
• Leading zeros
• Prefix
• Suffix
• Date or location code
• Skipped or reserved numbers

Confirm uniqueness

Software can generate a sequence, but the customer’s database must confirm that those numbers have not already been allocated.

Batch Production and xTool Studio

Current xTool Studio batch-processing tools can support spreadsheet data import, QR and barcode generation, and automatic numbering with prefixes and suffixes.

A controlled batch workflow should include:

• One approved spreadsheet
• One approved code template
• Locked dimensions
• Defined data mapping
• A test row
• Duplicate checking
• First-piece approval
• Batch scanning
• Packaging matching

Software automation does not replace verification

Every row can be imported correctly while the final physical codes remain too small, reflective, distorted or poorly contrasted.

Use Jigs and Fixtures for Consistent Positioning

A production jig holds each metal tag or product in the same location and orientation.

Benefits

• Consistent code position
• Faster loading
• Lower rotation errors
• Repeatable focus
• Reduced risk of engraving the wrong side
• Reliable matching between data and product

Jig identification

Mark each jig location clearly so software positions, spreadsheet rows and physical products follow the same sequence.

Do not mix unlabelled blanks

When every item carries different data, an incorrectly loaded blank can create a valid code on the wrong product.

Produce a Test Sample Before Full Production

The sample should use:

• Final metal
• Final surface finish
• Final code type
• Final code size
• Final encoded-data length
• Final laser process
• Final position
• Final cleaning method

Test representative extremes

Where data length varies, test both the least-dense and most-dense codes. The densest code may contain smaller cells and be more difficult to reproduce.

Test curved products separately

A flat metal sample does not represent the optical and focus challenges of a cylindrical product.

Scanning Is Not the Same as Verification

Functional scan test

Confirms that a particular phone or scanner can decode the symbol under a particular set of conditions.

Code verification

Measures defined physical and optical characteristics and assigns a quality result under controlled conditions.

A phone scan does not confirm:

• Compliance with an industry standard
• Performance across all scanners
• Acceptable module geometry
• Acceptable reflectance or contrast
• Long-term durability
• Correct data structure
• Direct-part-marking grade

Direct-Part-Marking Verification

Codes marked directly onto metal can behave differently from codes printed on white labels.

DPM challenges include:

• Uneven reflectivity
• Curved surfaces
• Low contrast
• Cell-size variation
• Surface texture
• Glare and shadows
• Material damage
• Contamination

ISO/IEC 29158

Directly marked QR and Data Matrix codes may be assessed using ISO/IEC 29158 or another standard specified by the customer.

Customer requirements should state:

• Symbology
• Encoded-data structure
• Physical module size
• Minimum quality grade
• Verification aperture or setup
• Lighting arrangement
• Reader type
• Acceptance sampling plan

Recommended Quality-Control Workflow

1. Verify the source data.
   Confirm that the serial number, URL, part number or structured data is correct.
2. Check for duplicates.
   Confirm that every supposedly unique record is unique.
3. Generate the symbol.
   Use the approved code type, settings and data structure.
4. Inspect the artwork.
   Confirm dimensions, module geometry, quiet zone and position.
5. Produce the first sample.
   Use the final metal, finish and laser process.
6. Scan and verify.
   Test with the intended reader and formal verification method where required.
7. Approve the physical sample.
   Record the material, settings, size, position and result.
8. Begin controlled batch production.
   Maintain the spreadsheet sequence and jig position.
9. Check codes during production.
   Do not wait until the entire batch is completed.
10. Match every item to its record.
    Confirm the human-readable number, encoded data and packaging label.
11. Save the final production report.
    Record accepted, rejected, replaced and unused serial numbers.

Maintain Production and Traceability Records

Recommended records

• Customer-approved spreadsheet
• Final code-generation file
• Final artwork template
• Material supplier and product code
• Laser settings
• Jig layout
• Approved physical sample
• Scanning or verification report
• Production date
• Operator
• Rejected serial numbers
• Replacement history

Do not reissue rejected numbers automatically

Depending on the customer’s traceability rules, a serial number used on a rejected part may need to remain recorded as cancelled rather than being reassigned.

Why Engraved Metal Codes Fail to Scan

Common Applications

What Affects the Price?

Pricing factors include:

• Metal product or blank
• Material and surface finish
• Code type
• Code dimensions
• Quantity
• One repeated code or different data
• Spreadsheet preparation
• QR or barcode generation
• Serial-number sequence
• Jig development
• Laser marking or engraving time
• Scanning or formal verification requirement
• Sorting and packaging
• Production report

Variable data costs more than one repeated code

Every item must be generated, matched, scanned and recorded individually.

Formal verification is a separate service requirement

An industrial verification report may require specialist equipment, controlled conditions and a defined standard beyond normal production scanning.

Review How Much Does Laser Engraving Cost in Malaysia? for a broader pricing guide.

Information Needed for an Accurate Quotation

Recommended Ordering Workflow

1. Define the business purpose.
   Confirm whether the code supports a website, inventory, warranty, traceability or industrial system.
2. Select the required symbology.
   Choose QR Code, Data Matrix or the required linear barcode.
3. Approve the data structure.
   Confirm the encoded information, prefix, serial-number rules and database format.
4. Confirm the material.
   Identify the metal, coating, surface finish and product shape.
5. Define code size and position.
   Include the physical dimensions, quiet zone and safe margins.
6. Prepare one approved spreadsheet.
   Remove duplicates, preserve leading zeros and lock the final version.
7. Generate the code artwork.
   Preserve square modules, finder patterns and required quiet zones.
8. Produce a physical test sample.
   Use the final material, size, encoded-data density and laser process.
9. Scan and verify the sample.
   Use the intended reader and formal standard where required.
10. Approve production.
    Confirm the physical sample, quotation, spreadsheet and packaging sequence.
11. Run controlled batch production.
    Use a jig, fixed sequence and intermediate scanning checks.
12. Complete final matching.
    Match each physical item, machine-readable code, serial number and packaging label.

What Image Magic Recommends

Important Code-Quality and Production Note

Frequently Asked Questions