Race-day fueling for ultras

Built from your runs, not someone else's average.

Targets honed from your own runs. Tolerance built at a pace you set. A race plan your crew can follow at every aid station, offline. Then what happens out there sharpens the next one.

The UltraFuel Today screen: yesterday's long run, the next race, and carb, fluid and sodium targets per hour

Your targets · per hour

65gCarbs

610mlFluid

500mgSodium

Free to start. No card.

Works with zero signal
·
Syncs with Strava, Apple Health, and Health Connect
·
Free to start

Your targets · per hour

65gCarbs

610mlFluid

500mgSodium

The failure mode

You trained for months. Then mile 60 happened.

The plan was in a spreadsheet on your laptop. The pace band smudged. Your crew is at the aid station guessing what you wanted, and you have no signal to tell them. Nothing about that failure is a fitness problem.

How it works

Plan it. Train for it. Execute it.

01Plan

Built from your runs, not a chart.

UltraFuel reads the training you already log and turns it into carb, fluid, and sodium targets for race day. Population averages are only the starting point. The targets sharpen as you log more runs. A backyard works too: give it the loop and the yards you are after, and the plan comes out per hour, because there is no finish time to build one against.

02Train

A gut that's ready before the start line.

Stomach trouble ends more ultras than tired legs do. UltraFuel builds gut training into your weeks of prep so your body knows how to take the fuel on race morning.

The Gut Training screen showing this week's carb rate and the choice to move up, stay, or back off

03Execute

Your crew already knows the plan.

Send them a link and it opens in any browser, with no app and no account. Crew who already have UltraFuel pair with one code instead. Either way they see what to have ready at every station, what time you're due, and how much, and it keeps working with no signal. Sharing with crew is part of Race Kit; the printable crew sheet is free.

The race-day tracker showing fueling on pace, with running carb, sodium, and fluid totals against plan

The same race on a crew member's phone, showing what to prepare for the next aid station

Offline-first

Built for places with no bars.

Your plan, your logging, and the live race tracker all work with zero signal. Data syncs in the background when a connection comes back. A dead zone never costs your crew an entry.

0 bars

needed to plan, log, or track

1 account

phone and web, same data. Plan on a big screen, execute on the trail.

The same account, on a big screen

Build the plan at a desk. Run it from your pocket.

Every aid station with its own carb, sodium, and fluid numbers, the time you are due there, the forecast, and whether your crew can reach you. Edit it on the web and the change is on your phone. Open the web app

The race plan on the web: an aid-station table listing each segment with its mileage, arrival time, forecast temperature, carbs, sodium, fluid, and whether crew can reach that station

Your runs come from where they already are.

Connect Strava, or pull workouts from your watch through Health Connect on Android and Apple Health on iPhone. Garmin, COROS, and the rest come through either one. Add a run by hand if you'd rather.

Strava
Health Connect
Apple Health
Garmin
COROS
Manual entry

Where this fits

You already have a watch, a coach, and a spreadsheet.

All three are good at what they do. Your watch records what happened. A training app analyzes it. A coach builds the block. A spreadsheet holds the plan until the moment you need it.

None of them execute the plan during the race, offline, with your crew looking at the same thing you are. That's the only job UltraFuel has.

Founder

Why I built this

I'm an ultrarunner with a stomach I've never fully trusted. It's cost me races. My wife was about to crew her first ultra, with no idea what I'd actually need at each aid station, and neither did I. UltraFuel is the answer to both: know what your gut can actually handle, and give your crew something better than a guess.

Your targets come from your own logged runs, and sharpen quickly as you log more. They're informational ranges, and they don't replace your doctor or dietitian.

CJFounder

Pricing

Free to start. Priced when it earns it.

What the free tier includes, and what Race Kit adds
	Free, permanently $0	Race Kit $69.99a year or $11.99 a month 14 days free
Runs from Strava, your watch, or by hand	Included	Included
Your fueling profile, built from those runs	Included	Included
The gut-training program	Included	Included
Insights: your averages, carb headroom, what worked	Included	Included
Races you can plan	One	Unlimited
Aid-station and drop-bag planning	Included	Included
Printable crew sheet	Included	Included
Solo race-day tracking	Included	Included
Crewing someone else's race	Included	Included
Arrival times modelled from your own pace	Not included	Included
Race-week carry plan	Not included	Included
Live crew tracking, and your live position	Not included	Included
Correlation analysis: what heat does to your numbers	Not included	Included

The 14-day free period applies to your first subscription. The correlation analysis also needs fifteen fueled long runs behind it, on either tier, because it has nothing to read before that.

The Insights tab showing average carbs, fluid, and sodium against target, the carb headroom left, and what set the athlete's best three runs apart

The analysis layer

Free tells you what happened. Race Kit tells you why.

This screen is the free tier: your averages against target, the headroom left on your carb ceiling, and what set your best runs apart. Race Kit adds the correlation layer on top, once you have logged enough long runs for it to say anything worth reading: how temperature moves your fluid needs, and where GI trouble clusters.

Start free. Add Race Kit inside the app, or on the web after signing in, when a race is on the calendar. Cancel anytime. See the full breakdown

Free, and not a demo

You can take a whole race through the app without paying.

Build the profile from your own runs. Train the gut for weeks. Plan the race with every aid station, print the crew sheet, and track the day itself. That is the free tier, with no card and no trial clock counting down behind it.

Creating a race, starting it, resetting it and finishing it all stay free. The free race is spent by the first fuel you log on race day, which means you can build a race and drive the tracker before you decide anything.

Questions

The things worth knowing first.

Does it really work with no signal?

Yes. Your plan, your logging, and the live race tracker all run on your phone with zero signal. Data syncs in the background when a connection comes back, so a dead zone deep in the mountains never costs your crew an entry.

What do I actually get for free?

Strava, Health Connect, and Apple Health sync, manual logging, the gut-training program, your full fueling profile, core insights, one race with a plan and a printable crew sheet, solo race-day tracking, and joining someone else's race as crew. Those stay free. Race Kit adds unlimited races, race-week carry plans, live crew tracking, and the deeper analysis layer.

Which watches and apps does it work with?

Connect Strava directly, or pull workouts from your watch through Health Connect on Android and Apple Health on iPhone. Garmin, COROS, and other watches that write to either one come through that way. You can also add a run by hand.

Is there an iPhone version?

Yes. UltraFuel is on the App Store and Google Play, with Apple Health import on iPhone and Health Connect on Android. The web app shares the same account and works in any browser, so you can build a race plan and read your numbers there too. Watch sync and race-day tracking live on the phone.

How does my crew see the plan?

Send them a link and it opens in any browser, with no app and no account. Crew who already have UltraFuel pair with one code instead. Either way they see what to have ready at each aid station, when you're due, and how much, and they can log what you actually took. Access covers that one race and expires 48 hours after you share it. Sharing with crew is part of Race Kit; the printable crew sheet is free.

Is my data private, and can I delete it?

We don't sell your data, show ads, or track you in the app. Crew members see only the race you share, never your training history. Export a full backup any time, and deleting your account removes everything across your devices and our servers. Details in the Privacy Policy.

What is gut training, exactly?

Stomach trouble ends more ultras than tired legs do. You raise how much fuel you take on long runs gradually, and UltraFuel shows you what each run actually handled so you can pick the next move. Race-day intake ends up being something you have already practiced. It's a training process, not a medical program.

Does it handle backyard ultras?

Yes. Pick the backyard format, give it your loop distance and the yards you are going for, and the plan comes out per hour rather than against a finish time nobody can know in advance. A loop is an hour, so per-hour targets and per-loop targets are the same number. The tracker works a yard at a time with the bell counting down, and the crew sheet becomes a camp page for every hour.

Do I need a crew to use this?

No. The fueling profile, gut training, race plan, and solo race-day tracker all work on their own. Crew sharing is there in Race Kit when you have one.

Your next race is already on the calendar.

Get the plan dialed before you're standing at the first aid station trying to remember it.

Free to start. No card.