Precision Fuel calculator alternative
Hourly numbers are free. The fuel card is the paid part.
Precision Fuel & Hydration publishes a free Fuel & Hydration Planner. It takes a couple of minutes and returns carbohydrate, fluid, and sodium per hour, plus a guide for hitting those numbers and a suggestion for which of their electrolyte strengths fits. Race Fuel Planner charges $7 for one event, or $19 once if you want another plan for the next race.
Their planner is here: precisionhydration.com/endurance-fueling. Use it if hourly targets are all you need.
What each one is for
The free planner is a calculator from a company that also sells drinks, gels, and electrolyte tablets. That does not make the hourly targets wrong. It does mean the product suggestions point at their range, and a sweat test — which they sell separately, at a price that depends on the location — is still the accurate way to know your sweat sodium.
Race Fuel Planner starts from the same kind of inputs: sport, distance or duration, finish time or pace, body weight, a sweat rate or a light/average/heavy estimate with temperature and humidity, caffeine, gut tolerance, and the foods you will use. Maurten, SiS, GU, and Precision Fuel are optional. Leave the brands blank and the list uses generic gels, chews, drink mix, and soft food.
The numbers are calculated in code and stay inside a 30–90 g/h carbohydrate range. Longer events sit higher. A sensitive gut sits lower, and anything above 60 g/h carries a gut-training note. Fluid is capped at 1 L per hour even if sweat loss is higher. The model writes a short tip. It does not change the grams.
What the $7 adds
The free preview on this site already shows the hourly carbohydrate, fluid, and sodium, and the first hour of the timeline. Paying $7 unlocks the rest of the timeline, a carry-versus-aid split when you enter station spacing, a shopping list with counts, the race-week carb-load and breakfast, a fuel card you can print or save as a PDF, and a CSV. Paying $19 lets you generate more plans later. It does not watch your watch and it does not replace a sweat test.
Side by side
| Precision Fuel planner | Race Fuel Planner | |
|---|---|---|
| Price | Free planner | $7 once, or $19 lifetime |
| Hourly carbs, fluid, sodium | Yes | Yes, in the free preview |
| Timed take-this table | A step-by-step guide | Every 15 or 30 minutes, with place on course |
| Carry vs aid stations | Not the point of the tool | Marked when you enter spacing |
| Shopping list | Suggests their own bottles and gels | Counts for Maurten, SiS, GU, Precision Fuel, or generic |
| Carb-load and breakfast | Not what the planner is for | Race-week amounts from body weight |
| Take it with you | On their site, plus a free call | Printable fuel card and CSV |
| Sweat sodium | Their sweat test is the accurate measure | An estimate unless you already know your rate |
When this is the wrong tool
If you want someone to look at your sweat sodium in a lab, book that test. If you want a free hourly estimate and you are happy to do the bottle math yourself, the Precision planner is enough. This page is not a copy of their product. If you are ill, pregnant, or managing a condition that changes fluid or sodium, talk to a physician before you follow either plan.
Questions
Race Fuel Planner is not medical advice and is not a sweat test. The numbers are estimates from what you typed. Practice any new amount in training. Stop for chest pain, confusion, or swelling. Drinking far beyond thirst for many hours can dilute blood sodium. If you have a health condition, talk with a physician before you follow this.