Caudal: Measure Fish by Photo

Measure your catch from a photo — no tape measure, no bump board, no scale. Caudal estimates a fish's length and weight from a single photo, so you can measure, log, and release in seconds. Point, shoot, done — or measure straight from a photo you already have. WHAT MAKES CAUDAL DIFFERENT Caudal's core measurement methods are patent-pending. Most measuring apps make you line up two points on the object while you're taking the picture — impossible with a live fish thrashing in your hands. Caudal doesn't. It finds the fish for you in the finished photo, and you only fine-tune afterward if you want to. And unlike other measuring tools, Caudal needs no reference object in the shot: • Calibrate your hand once against a wallet card or a sheet of paper. After that, your own hand is the ruler in every photo — nothing else required in frame. • On iPhone Pro, measure with LiDAR — no calibration, no reference object, not even your hand. Caudal even sees through the hand holding the fish, reconstructing the parts your grip covers so the whole fish is measured, not just the visible piece. MEASURE FROM ANY PHOTO A fresh catch or an old favorite from your camera roll — even fish you caught long before you downloaded the app. EVERYTHING ELSE ANGLERS WANT • Weight estimated from length using species-specific data • On-device species identification • Straight-line or body-contour length • A clean catch log that automatically records location, weather, moon phase, and tide • Works on any iPhone; LiDAR adds a calibration-free option on Pro models PRIVATE BY DESIGN Fish detection and species identification run entirely on your iPhone. Your photos aren't sent to any server to measure or identify your catch, and your hand calibration never leaves your device. FOR GUIDES, CAPTAINS, & LODGES Add your business name, website, and Instagram — every Caudal Card your guests share carries your credit, turning shares into referrals. BUILT FOR CATCH-AND-RELEASE Get a length and weight in seconds and get your fish back in the water fast. Caudal provides estimates for personal logging. It is not intended for determining compliance with fishing regulations, tournament eligibility, or official records.