CalBurndown is a calorie tracker built around a single screen — your daily burndown chart. The chart starts at your day's calorie budget and burns down to zero as you eat. Stay above the dashed line, and you're on pace for your deficit.
Here's everything you need to do to get useful numbers out of it.
1. Set your body
Open the web app, tap Settings, and fill in:
- Sex, age, height, current weight
- (Optional) goal weight and target weekly loss rate
This drives your BMR (basal metabolic rate) via the Mifflin–St Jeor equation. BMR is what you'd burn lying in bed all day, before any movement.
We don't ask for "activity level" multipliers — those guesses are the biggest source of error in most calorie trackers. We measure your activity directly, then calibrate against your weight after two weeks.
2. Pick a deficit
Default is a 500 kcal/day deficit, which targets roughly 1 lb of fat loss per week. Adjust in Settings → Goal.
If you're new to deficits, start at 250 kcal/day for two weeks. Smaller deficits are easier to sustain and easier to measure — a 500 kcal deficit on a noisy 2,200 kcal TDEE is a 23% gap, which weight fluctuations easily mask.
3. Log your first meal
Tap the + button. You have three ways to log:
- Type it — "two scrambled eggs, slice of sourdough, black coffee"
- Voice — say it out loud, same parser
- Photo — snap your plate; the AI estimates portions
All three feed the same nutrition estimator. See logging meals for accuracy expectations and when to use each.
4. Log a walk
Tap + → Log workout. CalBurndown handles:
- Walks, runs, hikes, bike rides (distance + pace)
- Rucks (with the Pandolf equation for weighted carry)
- Strength sets (reps × weight)
- Generic time-only entries
Once your watch syncs (coming with the mobile apps), this is automatic for most workouts.
5. Watch the chart
The headline number is what's left to eat today. The dashed line is your ideal pace. Green above the line means room to spare; red below means light dinner.
The "+X if pace holds" note next to the headline projects how much more budget you'll earn if you keep moving at today's rate.
Where to go next
- Install on iPhone — for full-screen + push notifications
- Install on Android
- How to set a calorie deficit — the math behind picking a number
- Reading the burndown chart — every line and what it means