# Tamper-evident QR labels

> Tamper-evident QR labels make the sticker-overlay attack visible, destructible vinyl fragments on removal, void laminates leave a printed warning behind, and holographic overlays cannot be cleanly replaced. They cost pennies per label in volume, and they only work when paired with a routine physical audit of every deployed code.

Source: https://useqr.app/docs/security/tamper-evident-qr-labels · Last reviewed 2026-08-21 · UseQR is free forever, no signup.

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## The attack this defeats

The most practical QR attack requires no technology at all: print a malicious code on a
sticker and paste it over a genuine one: the full anatomy is in
[stickers placed over real codes](/docs/security/qr-code-stickers-placed-over-real-ones),
and it is the engine behind [parking scams](/docs/security/parking-qr-code-scams) and
diverted payments. Tamper evidence attacks the attack: it cannot stop a sticker being
applied, but it makes both the removal of your label and the presence of a foreign one
visible.

## Label materials compared

| Material | What happens on tampering | Typical use |
|---|---|---|
| Destructible ("eggshell") vinyl | Deliberately low tensile strength, fragments into small flakes rather than peeling off in one piece | Payment standees, meters, asset tags |
| VOID laminate | Peeling separates the layers, leaving a printed VOID or checkerboard pattern behind on the surface | Seals, service labels |
| Holographic overlay | The shimmer pattern cannot be photocopied or reprinted; a replacement is visibly different | Tickets, certification marks |
| Direct print on the surface | Nothing to peel: an attacker must cover rather than replace, and coverage is easier to spot | Menus, signage, packaging |

Direct printing deserves more credit than it gets: a code printed into the artwork of a
sign has no label edges at all, so any label present is by definition foreign.

## Design-level tamper evidence

The material is half the defence; the artwork is the other half:

- **Print the destination domain in text under the code.** A substituted sticker must now
  also fake the text, and any mismatch between printed domain and the scanner's preview
  banner is caught by the reader.
- **Frame the code in your branding** so a plain white overlay square is visually loud.
  Frames and labels are covered in
  [frames and CTA labels](/docs/design/qr-code-frames-and-cta-labels).
- **Print the payee name large** on payment codes, so the name on the customer's
  confirmation screen can be checked against the sign.
- Keep the [quiet zone](/glossary/quiet-zone) inside the printed frame, so an overlay
  cannot hide behind "extra white space".

## The audit routine

Tamper evidence is a sensor, not a shield. It only works if someone looks. A workable
cadence:

| Surface | Check frequency |
|---|---|
| Public payment codes (standees, meters, chargers) | Weekly, and after any report |
| Customer-area codes (menus, tables, counters) | Monthly |
| Campaign materials (posters, flyers) | Once per campaign placement |

Each check takes seconds: run a finger over the code for edges, confirm the label is
intact, then scan with a [decoder](/scan) and verify the destination matches the registry
entry. Make it a named line on an existing checklist, audits that belong to nobody do not
happen. The organisational wrapper is in the
[enterprise QR policy](/docs/security/enterprise-qr-code-policy).

## Cost reality

Tamper-evident stock is cheap insurance: destructible vinyl and void-laminate labels run
to pennies per label at volume, a rounding error against the printed sign they protect:
the audit time costs more than the labels do. Print your codes as a
[sticker sheet](/sticker-sheet) and the only change is the stock you order from the
printer. For outdoor lifespan, combine with the materials advice in
[weatherproof QR stickers](/docs/print/qr-codes-outdoors-durability).

## Limits

Be honest about what this does not solve. A determined attacker can replace an **entire
sign** rather than overlay a label, and tamper evidence on the old sign is then
irrelevant; a stolen genuine label re-sited elsewhere still scans. For codes whose
authenticity truly matters, layer defences:
[signed payloads](/docs/security/signed-qr-codes-and-authenticity) for cryptographic
origin, tamper-evident stock for the physical layer, and the audit routine to close the
loop.

## FAQ

### What is a tamper-evident QR label?

A label printed on stock designed to show interference: destructible vinyl that
fragments on removal, laminates that leave a VOID pattern behind, or holographic overlays
that cannot be cleanly replaced. The goal is making sticker-swap attacks visible.

### Do tamper-proof stickers stop QR code scams?

They make the common overlay attack detectable rather than impossible. They work only
alongside a routine where someone actually inspects and rescans the codes; unwatched
tamper evidence catches nothing.

### How often should printed QR codes be checked?

Weekly for public payment surfaces such as standees, meters and chargers; monthly for
customer-area codes like menus; once per placement for campaign materials. Every check is
a feel for edges plus a scan to confirm the destination.

### What material is used for tamper-evident labels?

Most commonly destructible "eggshell" vinyl, which has deliberately low tensile strength
so it flakes apart on removal, and VOID laminates that separate to leave a printed warning
on the surface. Both cost pennies per label in volume.

## Try it

- https://useqr.app/sticker-sheet
- https://useqr.app/validate
- https://useqr.app/scan