How Sthenia estimates your grocery budget
Sthenia uses your budget to build a seven-day meal plan and its grocery list. The amount shown is an estimate based on the plan’s quantities and reference prices for France. Your budget is a target with a margin, not a guarantee of what you will pay in store. Here is what the calculation includes, how overspending is handled and what you need to check before shopping.
From your chosen budget to ingredient costs
You set a weekly target. Sthenia Pro builds meals and portions around your profile, goal and budget target. Ingredients from the meals are combined to calculate quantities and an estimated cost.
This calculation covers the ingredients in the plan. It does not automatically account for the full packs you need to buy or all the other products in your basket. To keep track of your spending, compare the list with what you already have and the pack sizes available in your store.
An ideal target and a 10% margin
The engine aims for the ideal budget you enter. Its threshold for an overspending warning is currently set at that target plus 10%. A plan between the target and this threshold may be presented without an overspending warning. Above the threshold, a plan may be offered with a warning.
So it is important to distinguish between “aiming for my budget”, “staying within the margin” and “never exceeding my budget”. Sthenia does not guarantee the last of these. If the proposed plan does not work for you, review the meals and purchases before following it.
References: [1]
Where do the prices come from?
An internal check on 23 October 2026 found that the database used for this calculation contained 111 manually entered reference prices. Of these, 88 had a source date of 1 December 2024, and 23 had no source date recorded. None of these entries included a source link.
These values are reference points for the calculation, not a record of current prices in your store. They are not synchronised with retailers in real time. This documentation describes the database checked on that date; it does not measure the difference between estimates and actual grocery receipts.
References: [1]
When an ingredient has no reference price
The database-based calculation is used when at least half of the ingredients are matched to a reference price. Below that level, the engine may fall back on an AI estimate. In the database-based total, an ingredient without a matching price does not contribute to the amount.
Partial coverage can therefore underestimate the cost. The number of ingredients matched and the accuracy of their prices are two separate issues: recognising a food does not prove that its price is up to date. Pay particular attention to missing products, brands and the purchases that make up the largest share of your list’s cost.
References: [1]
The cost of what you use versus what you pay
A recipe may use only part of a pack you need to buy. The pack price and the price per kilogram or litre answer different questions; Service Public distinguishes between these details in its guidance on price display in France.
Before heading out, identify the ingredients you already have, the quantities required and the packs you need to buy. Compare pack sizes for the same product, then check the total cost of your purchases. Our method for checking your list before shopping walks you through this step. No percentage saving or maximum difference between the estimate and the checkout total is guaranteed.
What this method helps you decide
Use the estimate to organise and compare your meals, then confirm your purchases against the prices you see. If your spending limit is strict, you still need to check your basket total. A low budget may mean revisiting variety, pack sizes or recipes; the tool should not be taken as proof that every constraint can always be met.
To understand the other part of the plan, read how Sthenia builds and checks a meal plan. Manual tracking remains free and unlimited; seven-day planning and the grocery list with estimated costs are part of the paid Pro plan.
References: [1]
Frequently asked
- Does Sthenia guarantee my grocery budget?
No. The engine aims for your target with a 10% margin and may offer a plan above that margin with a warning. The estimated amount does not guarantee the checkout total.
References: [1]
- Are these the prices at my supermarket today?
No. The database checked on 23 October 2026 is maintained manually and does not track store prices in real time. Check prices and available pack sizes before buying.
References: [1]
- Why might my basket cost more than the plan?
The calculation covers the ingredient quantities in the plan, whereas shopping may require buying full packs. Your store’s prices and partial ingredient coverage can also create a difference.
References: [1]
- Does free tracking include this planning?
Manual calorie and macro tracking is free and unlimited. Personalised seven-day planning with a budget and grocery list is part of the paid Sthenia Pro plan.
References: [1]
Sources
Also worth reading
- How Sthenia builds and checks a meal planTraining profile, estimated targets, food composition references and checks: understand how Sthenia generates meal plans and where its limits lie.
- Muscle gain on a budget: which foods should you choose?Compare foods, adjust your meals and organise your grocery shopping for muscle gain on a budget, with choices that suit your needs.
- Meal prep: how to calculate portions and groceriesCalculate portions for your planned meals and macros, keep raw and cooked weights separate, and build a grocery list that fits your budget.