Built by anglers, for anglers — free tools and expert knowledge for the sea fishing community
DeepBlue started with a simple frustration: too many sea fishing calculations were buried in scattered spreadsheets, outdated books, or paywalled apps. Anglers deserved better. In 2023, a small team of dedicated saltwater fishermen — engineers and educators by day — began building the free online toolkit we wished existed.
Today, DeepBlue offers more than 35 free online calculators covering the calculations every sea angler actually needs: line strength ratings, drag settings, leader lengths, casting distances, fish weight estimates, and tidal planners. We also publish expert fishing guides written by experienced anglers who've spent thousands of hours on the water.
We believe every angler — regardless of experience level or budget — deserves access to accurate, practical fishing tools and reliable knowledge. That means no paywalls, no account requirements, and no limits on how many times you use our calculators.
Our content is built on real fishing experience, peer-reviewed research, and consultation with marine biologists and tournament anglers. When we say a tool is scientifically grounded, we mean it.
We're a distributed team of sea fishing enthusiasts across the United States, United Kingdom, and Australia. Our core contributors include:
Line strength, drag settings, leader length, casting distance, fish weight, tidal times, water temperature conversion, and more.
In-depth articles on species, techniques, gear, weather, safety, and conditions — written by experienced anglers.
We specialize exclusively in saltwater and sea fishing — not freshwater. Every tool and guide is tailored for the ocean environment.
No accounts, no subscriptions, no premium tiers. Everything on DeepBlue is free, now and always.
We take accuracy seriously. Every calculator on DeepBlue uses peer-reviewed formulas and real-world testing. Our articles cite scientific literature where applicable and are reviewed by our contributor team before publication.
We do not accept payment for favorable reviews or placement. Our recommendations are based purely on real fishing value.
Have a suggestion for a new tool, found an error in an article, or want to contribute your own fishing knowledge? We'd love to hear from you.
Email us at admin@qtynip.com — we respond to every message within 48 hours on business days.
No sign-up needed. Just pick a tool and start planning your next fishing trip.
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