Butterfly & Moth ID: LepiDex

From a photo of a butterfly on a flower or a moth drawn to a light, this app suggests the closest species using AI that runs entirely on your device.

This app cannot tell you whether something is a pest or whether it needs to be dealt with. For that, please ask someone with real expertise.

[This guide knows 24 common species only]
12 moths, including Japanese Luna Moth, Gypsy Moth and Garden Tiger Moth, plus 12 butterflies, including Asian Swallowtail, Small White (Cabbage White) and Small Copper. If your photo isn't one of these 24, it says so honestly instead of forcing a guess.

[Two AI models: one for moths, one for butterflies]
Your photo is run through both models and the candidates are merged by confidence (moths: top-1 73.6% / top-3 93.8%; butterflies: top-1 72.9% / top-3 89.6%, each measured on all 12 classes).

[No overconfident guessing]
Up to 3 candidates, each with a 3-level confidence badge. When confidence is too low, no candidate is shown at all. The same photo always gives the same answer.

[A field guide you can read without taking a photo]
Original write-ups for all 24 species: how to tell them apart, life cycle, and a small fact worth knowing.

[Pricing]
Your first 7 days are unlimited as a trial. After that, 3 free identifications per day. One-time purchase removes the daily limit for good - this is not a subscription. No ads.

[About the training data]
Trained on CC0, CC BY and public-domain photos (1,860 photos / 356 photographers for moths; 2,018 photos / 392 photographers for butterflies). Photographer credits are listed in the app.

[Who it is for]
- Anyone curious about the butterflies and moths seen in a garden, a park or at the edge of a forest
- Summer-night watchers who want to look up the moths that gather around a porch light
- People who want a field guide that works without a signal, deep in the woods
- Families doing a nature project who want a simple, honest starting point

[How it works]
1. Take a photo of the butterfly or moth (or pick one from your album)
2. See up to three candidate species, each with a three-level confidence badge
3. Open the guide page to read how to tell them apart, how they live, and a small fact
4. Keep a note of the day you met it and look back later

[Questions people ask]
Q. What happens with a species that is not in the guide?
A. The app does not force a match. It says it could not tell, and you can browse the guide by hand instead.
Q. Does it need an internet connection?
A. No. Identification and the guide both run on your phone, so they work offline.
Q. Are my photos uploaded anywhere?
A. No. Photos and notes stay on your phone. There is no account and there are no ads.
Q. Is the answer always right?
A. No. It shows candidates, not a verdict. Look-alikes such as two clearwing-type hawk moths are hard to separate from a single photo, so the app adds a note when a pair like that comes up.