THE ENGINE

Every number has a reason.
And the working to prove it.

KEXBI does not guess your nutrition. It shows you how every number was built, from real formulas and named studies, with the working there to check.

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NO BLACK BOX

We don't ask you to trust the number. We show you how it was built.

Most apps hand you a target and hide the maths. KEXBI opens its own working. Plan Integrity runs a set of checks, traces your target back through each formula to the source, and even flags its own variance rather than burying it. Real formulas. Named studies. No plugs.

Plan Integrity screen: clear, 9 checks passed, and your target derived formula by formula with named sources
  • Every step is a formula. Lean body mass, resting metabolism, maintenance, your phase, training load, the final number. No plugs.
  • Every plan is checked. A set of integrity checks runs before the plan reaches you, including a safety floor that stops a plan ever asking you to eat too little to build.
  • We flag our own variance. When the plan lands a few calories off target, we tell you, show you why, and explain why we don't hide it.
HOW THE NUMBER IS BUILT

Worked out from your body, then built from three parts

Every target starts from your own measurements, your height, weight and body-fat, rather than a generic profile. Then it is assembled from resting burn, everyday movement, and the estimated cost of the day's training, and held above the fuelling floor.

65 kg
Bodyweight
22%
Body fat
50.7 kg
Lean mass
Female
Sex, where the formula needs it
A training day, built from three parts
2,178
calories, BMR + NEAT + training
BMR 1,465 NEAT 293 Training 420
Fuel for recovery: clear
under-fuelledgetting tight

On a rest day the training block is zero and the total drops to 1,758. Whatever the day, there is always enough fuel left for your body to turn the training into progress.

WHAT IT DOES FOR YOU

Fuelled to hit it.

The gains you train for only happen if you are fuelled to make them. Here is what KEXBI works out for you, and the research each decision stands on.

You can't build on empty.

Push hard on too little fuel and your body quietly stops adapting to protect itself. No new muscle, no faster pace, just a plateau you can't explain. KEXBI checks the energy left after training against what your body needs, and tops it back up before your progress pays for it.

The science

Energy availability, the metric most food and diet apps ignore while they optimise for a single calorie target.

See the evidence →

Finish as strong as you started.

Fading in the back half can be a fuelling problem, not just a fitness one. When the work gets hard your body burns carbohydrate faster than most people feed it, so KEXBI paces in what your gut can absorb while you go. You fuel the workout while it is happening.

The science

Carbohydrate paced to gut-absorption limits, the way endurance nutritionists fuel a race.

See the evidence →

Hold your muscle through a cut.

A deficit is when your body starts eyeing muscle for fuel. Most plans cut everything at once, protein included. KEXBI raises your protein as your calories come down and holds it there. You lose fat, and keep the muscle you fought for.

The science

Protein raised in a deficit to protect lean mass, not periodised down with your calories.

See the evidence →

Keeps up as you get fitter.

The number that fits you today is wrong within weeks. Training changes your body composition. Your energy needs move with it, and fixed targets drift out of date. KEXBI updates the target from your weight trend, rather than leaving you on a stale estimate.

The science

Adaptive TDEE, learned from your weight trend and intake, not a fixed formula.

See the evidence →
BUILT ON SCIENCE

364 evidence-based rules behind every decision.

KEXBI does not use generic formulas and leave the rest to you. It weighs recovery, timing and training demand, then turns them into today's food.

So your target is tuned to you, not left on a default

01
A baseline tuned to your body

Built from your lean mass when you've logged body fat, and from the Mifflin-St Jeor equation when you haven't.

Cunningham 1991 / Mifflin 1990
02
A target that tracks you

Learns your real maintenance from your weight trend, instead of trusting a fixed multiplier forever.

Hall 2011
03
The trend, not the daily jump

Reads the trend across your weigh-ins, so one water-weight morning can't move your plan.

KEXBI engine
04
Only your real days count

Only the days you actually logged feed the estimate, so thin data can't skew it.

KEXBI engine
05
Not the whole burn your watch claims

Your body offsets part of every workout elsewhere, so KEXBI discounts logged exercise rather than letting you eat back calories you never really spent.

Careau 2021
06
Eases off on diet-break weeks

On a scheduled diet-break week your deficit drops to true maintenance, easing the metabolic adaptation that a non-stop cut drives.

Byrne et al. 2018 (MATADOR)

So fuel lands when your body can use it

01
Energy when the workout needs it

Puts the bulk of your carbs around your workout, so there is fuel in the tank when you train, not sitting undigested.

Burgess & Eastman 2005
02
Bends to early or late types

Shifts fuel earlier or later depending on whether you run morning or evening, instead of one fixed schedule.

Roenneberg 2003
03
Cleared before you train

Predicts when a meal actually clears your gut, so you start fuelled but not weighed down.

de Oliveira 2014
04
Protein timed to actually build

Each main meal is dosed to trigger muscle growth, not just pad your daily protein total.

Areta 2013
05
Rebuild while you sleep

A pre-bed protein protocol feeds overnight muscle repair, so you wake recovered and ready to go again.

Res 2012 / Snijders 2015
06
Last night sets up today

After a short night your body handles carbs worse and builds muscle slower, so it trims carbs and lifts protein to match.

Buxton 2010 / Lamon 2021

Fuelled for the work ahead

01
Enough in the tank to build

Keeps enough fuel in the tank after training for your body to recover and adapt, so the hard work turns into real progress.

Loucks & Thuma 2003 / Areta 2020
02
Topped up before you start

Loads carbohydrate into the pre-training window, split across a meal and a fast top-up when one sitting can't hold it, so you start with a full tank.

Burke 2011 / Thomas 2016
03
Light enough to move

Caps food and fat before training so your gut isn't fighting you mid-workout.

de Oliveira 2014
04
Fuel the work, not survive it

Long workouts get a timed carb schedule, capped at the ~90 g/h your gut can absorb and using glucose plus fructose to push past the single-sugar limit, so you finish strong instead of fading.

Jeukendrup 2014 / Stellingwerff 2014
05
Fluid you can actually absorb

Replaces sweat only at the rate your gut can take it, up to ~800-1200 ml/h, no more.

Jeukendrup 2014
06
Low fuel never hides

When your logging is thin, it keeps under-fuelling visible instead of assuming you're fine.

KEXBI engine

So the plan keeps up as you change

01
Catches the slowdown that stalls you

In a cut your metabolism quietly drops and progress stalls. KEXBI tracks the drop and holds your real deficit, so you keep moving where static plans die.

Careau 2021 / Hall 2011
02
Nothing changes behind your back

Your week's plan is built ahead. When KEXBI spots something impactful, a rough night, an unplanned workout, it shows you the change and you apply it with one tap.

KEXBI engine
03
Won't chase bad data

It checks your log is reliable before acting, and holds your last good target rather than drift on noise.

KEXBI engine
ENDURANCE FUELLING

Your longest workouts, fuelled by the hour.

The longer and harder you go, the more fuelling decides whether you finish strong or fall apart. KEXBI runs the intra-workout fuelling a specialist endurance nutritionist would, dialled to your gut and the workout ahead.

KEXBI in-app fuelling timeline for a marathon: pre-load feeds and timed during-event gels, each dose held under the gut absorption ceiling
  • It won't over-fuel a short workout. Under an hour, or an easy hour, you get water. Carbs only appear once a workout is long or hard enough to actually need them.
  • Capped at what your gut can take. Every dose is held under the ~90 g/h absorption ceiling, so you're fuelled, not bloated.
  • Two sugars, not one. Glucose plus fructose ride two separate gut transporters, unlocking higher absorption than glucose alone can reach.
  • A timed feed schedule, not "grab a gel." Real checkpoints across the workout, dosed to practical whole servings.
  • A starting protocol, not a fixed rule. Gut tolerance is trainable, so rehearse your race fuelling in practice, and KEXBI adjusts to what you can actually take.
Jeukendrup 2014 · Stellingwerff 2014 · Burke 2011
Read the science →
THE FUEL DATABASE

A food database built to know timing

A calorie count is just the baseline. The real advantage is knowing how a food behaves in your body, and when it belongs in your day. Over 9,000 whole foods are enriched to this depth, alongside more than 2.7 million branded products. Every value is drawn from real sources: USDA, CoFID, BLS, Open Food Facts and manufacturer labels, plus glycemic-index data from the University of Sydney. The method and confidence behind each one are shown. Scan something new and it resolves against that database, then joins the enriched corpus, which grows by roughly a thousand foods a week as items graduate through our agents and your barcode scans.

9,000+
foods enriched
2.7M+
in the database
11
eating windows scored

What does enriched actually mean? The same tub of whey protein, in both worlds:

A tracker sees
Whey protein, per 100 g
Calories360 kcal
Protein90 g
Carbs and fat1 g and 0 g
Anything elsenothing
KEXBI sees
The same tub of whey
What it isfast-digesting lean protein
Best windowthe hours after training, not a 30-minute rush
Muscle repairone scoop meets your leucine target
On the gutsits easy after hard training
A real servinga 30 g scoop, not 100 g

Cottage cheese

Slow-release protein
belongs ↓
before bed

Feeds your muscles slowly through the overnight fast.

Whey shake

Fast-digesting protein
belongs ↓
after training

Fast protein for the hours after hard training, when it is easiest to hit your recovery dose.

Energy gel

Pocketable, fast carbs
belongs ↓
mid-run

Fuel you can carry, for the middle of a long effort.

And it knows the practical things about every food, the ones that decide whether a plan is realistic:

Take a bowl of oats
KEXBI understands it like this
Raw or cookedadjusts to how you cook it
How fast it digestssteady, not a spike
Before a workoutsits comfortably
A sensible portiona real bowl, not a mountain
Nutrients trackedvitamins and minerals, cooking-adjusted
Cooked, not raw
The numbers match your plate
Rice roughly doubles when cooked, meat loses about a quarter. KEXBI fuels against the food actually in front of you, not a raw-weight guess.
Read, not guessed
It reads real ingredients
A plant-based shake is understood as plant-based, never mistaken for whey because of its name. Allergens and diet are handled properly.
Right portions
A drizzle, never a bowl
The same avocado is a generous half when it is the star and a thin slice as a garnish. Oil is a drizzle. Every serving reads as real food.
UNDER THE SURFACE

26 systems. One daily answer.

Recovery, timing, hydration, energy availability, body composition and the food you actually have all get checked before the day is set.

Signals

Sleep, training, weigh-ins, hydration, body composition, and food reality all describe different parts of the same day.

Specialist systems

Each system resolves one layer of the problem: energy, timing, safety, adaptation, or recovery.

One plan

You can inspect any one system, but you never have to. The 26 resolve into one clear protocol for the day ahead.

01

Recovery Systems

Sleep architecture, readiness, and overnight repair shape what the day can support before anything is prescribed.

readiness / sleep / overnight repair
02

Timing Systems

Circadian phase, meal timing, and sleep impact decide when fuel and hydration should land.

circadian timing / phase shifting / sleep impact
03

Fuel Systems

Energy needs, protein distribution, and training demand shape what the day requires, not just a generic calorie target.

TDEE / protein pulse / load split
04

Safety Systems

Energy availability, hydration caps, and pre-workout limits keep every plan inside what your body can take in and use, so every gram works for you.

energy availability / hydration cap / gastric limit
05

Adaptation Systems

The engine rewrites the day when training load, weigh-ins, adherence, or real-life conditions change.

AEE delta / fallback logic / trust gating
06

Food Reality Systems

Pantry logic, meal rotation, and practical constraints keep the plan grounded in what the user can actually do.

pantry / diversity / practical execution

You can trace any one system, but you never have to. The value is that they resolve together, and every number still arrives as one answer you can check.

364
evidence-based rules governing the day
89
peer-reviewed sources behind the science
92
core calculations behind the plan
26
systems behind one daily answer

Built on work by Burke, Areta, Jeukendrup, Aragon and Schoenfeld and dozens more. Every rule traces to a named source you can read.

KEXBI's safety limits are guidance to keep you fuelled, not medical advice or a diagnosis. If something feels off, speak to a clinician or a sports dietitian.

A runner pausing by the track between workouts

Precision fuelling
for your training.

BETA UNDERWAY

Ready to stop guessing?

Cohort 001 is in testing now. Join the list for early access before public launch, and we'll email you the moment your place is ready.

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