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The tools,
free and unlocked.

Small, honest calculators that answer one question each. Start anywhere. When you want the whole race handled in one schedule, the full plan is one click away.

Start here

Your full fueling plan

Six questions and you get the whole race: carbs an hour, fluid, sodium, and every feed placed on your actual course. This is the one that replaces the guesswork.

75 g/hr · 11 feeds · every one on a real aid station
Example for a 3:30 Boston runner — yours is computed from your answers.
Build my plan · 3 min →

Caffeine dose calculator

How much actually helps, and where more just buys you jitters. Your dose from your body weight, on the evidence-backed 3–6 mg/kg range.

A 70 kg runner lands near 210–420 mg
Most runners get the timing wrong, not the dose — taken at the gun it peaks by mile 8.
Work out my dose →

Drink-mix builder

How strong to mix your bottle, and what that means in grams per hour. Concentration is what decides whether your stomach can empty it at all.

6% is where most on-course drinks land · we cap plans at 8%
Past 8% the gut empties slower than it absorbs.
Build my bottle →

What's your fueling type?

Five questions, one named type, and the science behind why your gut behaves the way it does — plus the products that suit it.

High-Sweat Heavy Hitter · Caffeine-Sensitive Sipper · Long-Haul Diesel
Five types, each with its own fuelling failure mode.
Find my type →

Find my fuel

Answer five quick questions and the whole database re-ranks around your race, your sweat, and your gut. Or skip the quiz and filter it yourself.

Matched on carb target, sodium need and gut tolerance
Sorted by evidence, never by who pays us.
Match me →

The fuel database

Every gel, chew, bar, drink mix and electrolyte we've verified against its own label. Carbs, sodium, caffeine, glucose:fructose ratio, cost per 25 g of carbs.

163 products, each checked against the label
Compare any two side by side.
Browse the database →

Every tool here is free and needs no account. They each answer one question well — but carbs, fluid, sodium, caffeine and the course all interact, so a number in isolation only gets you part of the way. The plan is where they resolve into one schedule.

Or skip the one-offs and get the whole race

One schedule that already accounts for your course, your sweat rate, your gut ceiling and the forecast — then guides you through it live on race day.

Build my plan →