Read the clues.
Narrow the cause.

PestDecoder starts with what you actually found—droppings, frass, skins, holes, stains, sounds or damage—then ranks the most compatible household pests and tells you what does not fit.

Decode what you found Compare any two candidates

Private in your browserTransparent rule matchingPrimary-source safety guidanceInitial U.S./Canada scope

Evidence workstation · local session

What did you find?

01 / 06

Droppings

Eggs and cases

Shed skins

Frass and pellets

Wings and swarmers

Holes and openings

Nothing is uploadedContinue →

31evidence-based pest profiles

12physical clue categories

30direct lookalike comparisons

0photos uploaded or accounts required

A different starting point

Most pest libraries ask you to name the pest first.

PestDecoder reverses the workflow: start with the physical evidence, then use location, scale, pattern, context and timing to reduce uncertainty.

SIZEROOMTIMEPATHCONTEXT

An explainable shortlist, not a magic answer

Every result separates aligned clues, contradictions and the next observation with the highest information value. The score is explicitly a clue fit—not a diagnosis or probability.

Mouse route

Cockroach harbor

Comparisons built around decisions

See what actually separates mouse droppings from cockroach evidence, termite frass from carpenter-ant debris and more.

Room-specific inspection paths

Check the highest-signal areas first without tearing apart the room or contaminating evidence.

Private by design

No account, photo upload, tracking profile or lead form is required to use the core product.

Matches

Conflicts

Contradictions stay visible

A useful identifier should show why a candidate may be wrong—not hide uncertainty behind a confident label.

Start from the evidence

Choose the sign you can describe most reliably.

Do not touch or move an unknown material just to identify it. Photograph it in place beside a ruler when safe.

Droppings

Shape, ends, texture and placement can narrow rodents, cockroaches and bats without touching the material.

7 candidate profiles

Inspect this clue

Eggs and cases

Capsules, clusters and attached cases can separate cockroaches, moths, bed bugs and flies when scale and placement are documented.

8 candidate profiles

Inspect this clue

Shed skins

Cast skins preserve body shape and are often more diagnostic than a fleeting live sighting.

6 candidate profiles

Inspect this clue

Frass and pellets

Pellets, sawdust-like debris and mixed wood shavings can separate termites, carpenter ants and wood-boring beetles.

5 candidate profiles

Inspect this clue

Wings and swarmers

Equal wing length, body shape, season and the point of emergence help separate termites, ants and seasonal flies.

4 candidate profiles

Inspect this clue

Holes and openings

Diameter, edge quality, material and debris below an opening can distinguish insect exit holes, rodent routes and wildlife entry.

8 candidate profiles

Inspect this clue

Browse all 12 evidence types

Both favor damp lower spaces; American cockroaches are reddish, larger and warmer-route oriented, while Oriental cockroaches are darker and tolerate cooler wet sites.

CockroachCockroach

Open comparison

The evidence can be useful without pretending it is certain.

PestDecoder is built to help a homeowner, renter or property manager organize observations, avoid unsafe handling and know when professional inspection is the right next move.

Sources are public and visibleAdvertising cannot change rankingsHigh-consequence cases escalate earlyPages have distinct search intent

Use the tool now

Six clues. A transparent shortlist. A safer next observation.

Your answers stay in the page and can be shared as a URL without storing an account.

Start decoding

Read the clues.Narrow the cause.