What you're building
A calorie tracker inside Claude Projects that reads photos of your food, estimates your macros, and shows you your running daily totals with a percentage breakdown after every entry. No database. No templates. No app to download.
Your goals are baked into the setup: 1,800 calories max, 180g protein, 10,000 steps per day, and three weightlifting sessions per week.
Step 1: Create a Claude Project
Go to claude.ai and click Projects in the left sidebar. Create a new project and name it anything you want. "Nutrition Coach" works.
Projects give Claude permanent instructions that apply to every conversation inside that project. You paste the system prompt once and it runs automatically every session.
Step 2: Add the system prompt
Inside your new project, open the project settings and find the Project instructions box. Paste this in exactly as written:
You are tracking my daily food intake. I will send you photos or descriptions of everything I eat throughout the day.
My daily goals:
- Calories: 1,800 max
- Protein: 180g
- Steps: 10,000 per day
- Workouts: 3 weightlifting sessions per week
Every time I log food, respond with:
What you identified: [food item, estimated portion size, calories, protein, fat, carbs]
Daily running total:
Calories: X / 1,800
Protein: Xg / 180g
Fat: Xg
Carbs: Xg
Macro split (% of today's calories):
Protein: X%
Fat: X%
Carbs: X%
When I say "it's a new day," reset all totals to zero and start fresh.
Keep responses short. No explanations unless I ask.Your goals are already baked in. You don't need to configure anything when you start a new conversation.
Step 3: Log a meal
Take a photo of your food and paste it directly into the Claude Projects chat. You don't need to describe anything unless the photo is unclear. For restaurant meals, tell Claude the restaurant name and exactly what you ordered. The more specific you are, the more accurate the estimate.
What a response looks like
What you ate: Grilled chicken breast (~6oz), brown rice (~1 cup cooked),
broccoli (~1 cup), olive oil drizzle
Meal: 610 cal | 60g protein | 15g fat | 56g carbs
---
Daily running total:
Calories: 610 / 1,800
Protein: 60g / 180g
Fat: 15g
Carbs: 56g
Macro split:
Protein: 39%
Fat: 22%
Carbs: 37%Step 4: Start a new day
Open a new conversation inside the project and type "it's a new day" as your first message. Claude resets all totals to zero and you start logging from there.
One conversation per day is the intended workflow. Claude Projects remembers your instructions permanently but does not carry running totals across separate conversations.
Other things you can say
daily total
Shows your running totals at any point without logging a new meal.
what should I eat
Claude looks at your remaining calories and protein and suggests what to eat next.
I hit my steps today / I did a workout today
Claude logs it and tracks your weekly progress against your step and workout goals.
undo that
Removes the last logged meal if you made a mistake.
A few things to know
Photo estimates are close but not exact. Whole foods and simple meals are highly accurate. Restaurant dishes with sauces, mixed ingredients, or unknown portions will have more variance. For anything where accuracy matters, describe the portion size in addition to the photo.
The macro percentages show the split of calories by source, not the percentage of your daily goal. Protein at 4 cal/g, carbs at 4 cal/g, fat at 9 cal/g.
