Built for self-coached lifters cutting or recomping. Every feature ties back to one idea: the right answer for this day, given your whole week.
Just type what you ate. Kai parses the food, estimates portions, looks up macros (USDA database for whole foods), and writes a structured entry to your day.
Examples Kai handles: "two scrambled eggs and a piece of toast", "chipotle bowl double chicken no rice", "12oz cold brew with oat milk".
Take a photo of your plate. Kai's vision model identifies every food, estimates portions from visual cues, and logs the meal — with a one-line summary of what it saw so you can correct anything.
Works on restaurant plates, home cooking, takeout — anywhere there's a real photo.
Tell Kai a stable fact once and it sticks: dietary preferences, training schedule, injuries, life context. Kai uses these to personalize advice over weeks and months — not just one session.
Your starting targets come from a science-based calculation. After a week of weigh-ins, Kai checks your actual trend and proposes adjustments — slow loss, stalled progress, faster than expected — all caught early.
Tell Kai how many days you can train, what equipment you have, your experience and any injuries. FitNav builds a weekly split where every week covers squat and hinge, push and pull — and picks exercises that fit your gear and your joints. Want a change? Ask for a refresh and the plan actually switches things up.
Kai never rewrites your plan without your OK.
Open today's session and tick off sets with weight and reps as you go. Every change is saved on your phone first, so a dead signal, a crash or a killed app never loses a set. When you finish, the session lands in your log and feeds your next workout.
FitNav reads your logged history and works out the next load and rep target for each lift: add weight when you've earned it, build reps when you haven't, ease back after two misses at the same weight. If a lift goes three sessions without progress, Kai flags the stall and offers a swap or a deload.
Bench taken? Shoulder complaining? Ask for a swap and Kai offers up to three substitutes for the same movement that fit your equipment, injuries and level, with sets and reps re-set for the new exercise.
Short on time? Say "I only have 30 minutes" and Kai trims today's session — main lifts stay, accessories get supersetted, optional work goes first — without touching your saved plan.
Beat up? Kai can propose a deload week with roughly 40% fewer sets and lighter loads. It only starts when you say yes.
Once a week Kai looks back at your training: sessions done vs. planned, hard sets per muscle against your weekly targets, new PRs, exercises you keep skipping, and lifts that have stalled. It suggests next steps — simplify, swap, deload — and waits for your go-ahead.
Save a recipe with per-portion macros and later just say "I ate the cookie I made." Add packaged foods to your pantry with exact label macros, so Kai logs the real numbers instead of estimating.
Opt in to share your location and Kai finds nearby chain restaurants where it can look up real macros. It only suggests places it has data for — it won't make numbers up.
Location is only used when you've allowed it.
Log walks, runs and steps in plain language. Track your weight and body-fat % (caliper, DEXA, BIA and more). When your body fat changes, Kai shows how your targets would shift and only applies the change after you agree.
Logged activity is for your records — it doesn't automatically raise your calorie budget.
Daily history, consecutive-logging streak, weight chart with 7- and 14-day moving averages. Kai surfaces what matters; you don't have to dig.
A nudge in the evening if you haven't logged dinner, and a Sunday check-in with Kai for your weekly review. They're push notifications, and you're asked for permission first.
Talk to Kai while you cook or walk instead of typing. Voice isn't in the first release; we're watching how many people ask for it.
Real situations Kai is built to handle. Not "log a food" — actual decisions you make every day.
A real coach is $100+ a month. FitNav is a tenth of that — and gets smarter the longer you use it. Free for 14 days.
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