Trout Weight Calculator
Estimate the weight of a trout from its length and girth so you can measure it, log it and let it go.
Open tool : Trout Weight Calculator
Field Tools
First Rise Fly Fishing Tools
Practical calculators, charts and river tools for better days on the water.
Estimate the weight of a fish before you release it. Match tippet to the fly on your vise. Read water temperature, work out a leader, size a rod, or turn a gauge reading into something you can picture. Free to use, nothing to sign up for.
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The four tools anglers reach for most often.
Tippet Size Calculator
Match tippet size, diameter and typical breaking strength to the fly you are about to tie on.
Open tool : Tippet Size CalculatorTrout Water Temperature Guide
Read water temperature and know when trout feed, when they slow down and when to leave them alone.
Open tool : Trout Water Temperature GuideFly Fishing Hatch Chart
A season by season look at the major mayfly, caddis, stonefly and terrestrial hatches.
Open tool : Fly Fishing Hatch ChartEvery tool
Search by name, or filter by category.
Trout Weight Calculator
Estimate the weight of a trout from its length and girth so you can measure it, log it and let it go.
Open tool : Trout Weight CalculatorTippet Size Calculator
Match tippet size, diameter and typical breaking strength to the fly you are about to tie on.
Open tool : Tippet Size CalculatorFly Size to Tippet Matcher
Look up the balanced tippet range for any hook size from 2 down to 28.
Open tool : Fly Size to Tippet MatcherFly Fishing Leader Calculator
Work out a leader length and taper that suits the water, the fly and the conditions in front of you.
Open tool : Fly Fishing Leader CalculatorLeader Formula Builder
Build a hand tied leader formula section by section using the 60/20/20 method.
Open tool : Leader Formula BuilderFly Line Weight Chart
The AFFTA grain weight standard for fly lines 1 through 12, and what each line is normally used for.
Open tool : Fly Line Weight ChartFly Rod Weight Guide
Find the rod weight that fits the water you fish, the fish you chase and the flies you throw.
Open tool : Fly Rod Weight GuideFly Reel Backing Calculator
Estimate how much backing sits behind your fly line on a given reel before you spool up.
Open tool : Fly Reel Backing CalculatorTrout Water Temperature Guide
Read water temperature and know when trout feed, when they slow down and when to leave them alone.
Open tool : Trout Water Temperature GuideFly Fishing Hatch Chart
A season by season look at the major mayfly, caddis, stonefly and terrestrial hatches.
Open tool : Fly Fishing Hatch ChartRiver Flow Calculator
Estimate discharge in cubic feet per second from stream width, average depth and surface velocity.
Open tool : River Flow CalculatorCFS Converter
Convert cubic feet per second into cubic metres per second, gallons per minute and other flow units.
Open tool : CFS ConverterNo tool matches that search.
Useful on the water. Useful before you leave home.
Most of these calculations get done badly in a parking lot at five in the morning, or not at all. A leader gets guessed at. A fish gets called five pounds because it felt heavy. Tippet gets tied on because it was already on the spool.
These tools do the arithmetic so you can spend the thinking on the water instead. They are built to be read on a phone with cold hands and no signal to spare.
They do not replace local knowledge, state regulations, a guide who was on that river yesterday, or a current gauge reading. Where a tool touches fish health or safety it says so plainly and points you back at the people who set the rules for your water.
River tools, coming next
River specific hatch charts are in progress. Each one will live at its own address so it can be found, bookmarked and used on the bank.
- Madison River Hatch ChartMontana Live
- Gallatin River Hatch ChartMontana In progress
- Yellowstone River Hatch ChartMontana and Wyoming In progress
- Firehole River Hatch ChartYellowstone National Park In progress
- Snake River Hatch ChartWyoming and Idaho In progress
Want a river added to the list? Tell us which water you fish.