◐ new Β· fuel copilot v2Ξ” G-Flux stable

Run for the snacks.
Plan for the bonk-free part.

CarbTrip is a fueling copilot for runners who mostly want an excuse to eat gummy bears at mile 8. We map your route, your favorite snacks, and your metabolism β€” and tell you exactly when to chew.

60 g/hr
target intake
0
bonks (median)
12.4 mi
sample run
Gummy bearsSwedish fishMaurten gel
Mile 8.2 Β· next snack
🐟 4 Swedish Fish
Because your liver glycogen is about to file a complaint.
Tested on 4,812 hungry miles🍬 Snacks logged: 21,904Bonks prevented: yesCited in 0 peer-reviewed journalsLoved by 3 dogsΞ” G-Flux stable
β—‡ what it does

A fueling copilot that actually gets your snack drawer.

Six small tools, one big idea: the best fuel plan is the one you'll actually put in your mouth.

🍬F-01

A snack library that knows you

Rate treats by sweetness, texture, and how fast they hit. CarbTrip picks the ones you'll actually chew at mile 9 β€” not the gel you keep pretending to like.

Browse snacks
πŸ—ΊοΈF-02

Route-aware fuel timeline

Import a GPX, sketch a loop, or just describe today. We drop snack pins mile-by-mile, drag-to-retime, and rewrite the 'why' note when you shuffle them.

Plan a run
πŸ“ˆF-03

Bonk-zone projections

A live energy curve estimates when your glycogen will file a complaint. Red bands = plan a snack here. Or don't. We're not your coach. (We kinda are.)

See the map
⌚F-04

Watch-friendly haptics

A gentle buzz at mile 4.5 that means 'gummy bear, now.' No looking at your wrist mid-stride, no third-party math.

πŸ““F-05

Recap + logbook

Log how you felt (bonk / almost / crushed), and CarbTrip retunes future targets. Compare runs side by side β€” planned vs. actual, week over week.

Open logbook
🧠F-06

Bring-your-own ChatGPT

One tap opens a pre-filled prompt that stress-tests your plan against your goal, elevation, and fueling history. Human + LLM + gummy bear.

Β§ 03 Β· the science-y part

Sports nutrition, minus the influencer.

CarbTrip's model is built on the same carbohydrate-oxidation research your favorite sports dietitian keeps citing β€” glucose-fructose 2:1 blends, 60–90 g/hr for >90 min efforts, gut-training progression. We just wrapped it in a UI that respects your love of Swedish Fish.

  • ref Jeukendrup, 2014 Β· multi-transporter carb oxidation
  • ref Costa et al., 2017 Β· exercise-induced GI syndrome
  • ref Burke, 2021 Β· fueling for the work required
system telemetry
Nerd Stuff Panel
live sample
Ξ” G-Flux
+18 kcal · hr⁻¹
Muscle glycogen
72% Β· est.
CHO oxidation ceiling
78 g · hr⁻¹
Gut-training index
3 / 5
Blood glucose (proxy)
5.4 mmol · L⁻¹
Bonk probability
0.11 @ mi 11.2

* Numbers derived from your run history + published carb oxidation curves. Not medical advice. Definitely not an excuse to skip breakfast.

β—ˆ notes from the field

Runners, but honest about the candy.

"I used to bonk at mile 10 like clockwork. Now I bonk at mile 22, which is a much fancier problem."
Marta K.
half-marathoner Β· Berlin
"It told me to eat a Sour Patch Kid at mile 6 and I've never trusted software more."
Devon R.
50k finisher Β· Oakland
"Finally, a running app that doesn't shame me for putting gummy worms in my flip belt."
Priya S.
marathon PR Β· Brooklyn
Β§ pricing

Free to fuel. Pro for the science-y bits.

Free
$0/ forever
πŸ₯¨
  • βœ“ Snack library + personality stats
  • βœ“ Route drawing + describe-today
  • βœ“ Fuel timeline with drag-to-retime
  • βœ“ Post-run recap + logbook
Start free
Snack Pro
$6/ month
Popular
  • βœ“ Everything in Free
  • βœ“ Bio-analytical Nerd Stuff Panel
  • βœ“ Bonk-zone projections + energy curve
  • βœ“ Apple Watch haptics + live prompts
  • βœ“ Redemption-run auto-planning from recap misses
  • βœ“ Beautiful share cards (route + recap posters)
Go Pro

14-day free trial Β· cancel any mile

β—‘ questions we've been asked

Real questions from real snack people.

Is this actually science, or just gummy bear propaganda?+

Both, and we're proud. The fueling math tracks published carb-oxidation research; the vibes are ours.

Do I need a fancy watch?+

No. CarbTrip works fine as a phone-in-armband experience. Apple Watch haptic prompts are a Snack Pro nice-to-have.

What if my favorite snack isn't in the library?+

Add it. Rate its sweetness, chew factor, and how fast it hits β€” CarbTrip works out the carbs so you don't have to.

Will this replace my coach / RD?+

Nope. But it'll make the fueling conversation with them 10x more specific β€” and it'll stop you bonking at mile 9 in the meantime.

β—† ready when you are

Your next long run deserves a better snack plan.