Fish Ruler Size Measure Catch

You landed the fish. Now how long is it — and will you remember by next season?

Reaching for a tape measure with wet hands, holding a thrashing fish flat, keeping the tape straight — it never works the way it should, and the fish is losing time out of the water while you fumble.

FishRuler turns your iPhone into the measuring tool you actually have with you. Point the camera at your catch, tap the nose, tap the tail, and the length appears on screen in centimeters. Save it to your log with one tap, and it's never lost again.

HOW IT WORKS
• Tap two points — nose and tail — and read the distance between them
• Missed the spot? Drag either marker to fine-tune without starting over
• A line is drawn between the two points so you can see exactly what was measured
• Save the catch with a photo, species, spot and date, or hit Reset and move on

YOUR CATCH LOG
• Every saved catch lives in a scrollable log — photo, species, length, spot and date, all in one card
• FishRuler tracks your personal best per species automatically. Beat your record and the app tells you right away
• Best-ever catches stand out in the log so your top fish are always easy to find
• Turn any catch card into a single image, ready to share

WHY ANGLERS LIKE IT
• Nothing to unroll, nothing to hold flat, nothing to lose overboard
• Fast enough to measure and release quickly
• Works fully offline — no signal needed at the lake, river or jetty
• No account, no sign-up. Your log stays on your device
• Useful beyond fish, too: measure gear, coolers, boat fittings or anything else in front of you

BEFORE YOU BUY — DEVICE REQUIREMENT
FishRuler measures using the LiDAR scanner, so it needs an iPhone that has one — iPhone 12 Pro / Pro Max or later Pro models. On a device without a LiDAR scanner the app will tell you it cannot measure. It also requires iOS 17 or later, so please check both your model and iOS version before purchasing.

ABOUT ACCURACY
Readings are real-world estimates produced by the device's depth sensor. Good light, a steady hand and a fish lying flat give the best results. Treat the number as a practical field measurement — for tournament rules, legal size limits or official record submissions, always confirm with the measuring device that the rules require.

ABOUT THE SIZE REFERENCE NOTE
For a small number of species and regions, FishRuler can show a reference note if a catch falls outside the usual take-home size range. This is for your information only — it is not a full or authoritative list of regulations, and it does not replace checking current rules with your local fisheries authority before you keep a fish.

One purchase. No subscription, no ads.