How to Calculate Supply on Wildberries?

Supply to Wildberries is calculated so that there is enough stock until the next replenishment, but without excess inventory. For each item, the number of units sold during production, delivery, and planned reserve is calculated, a safety stock is added, and what is already in stock and in transit is subtracted.

What data is needed to calculate supply to Wildberries

To calculate supply to Wildberries, data is collected separately for each item: average sales, remaining stock, goods in transit, and replenishment timelines. One general scheme for the entire assortment does not work because different items sell at different speeds and require different supply intervals.

To correctly calculate the supply, you need to prepare:

average daily sales;

current remaining stock at each WB warehouse;

goods already shipped but not yet accepted;

production or procurement lead time;

delivery and acceptance time;

safety stock size.

All subsequent calculations are based on these indicators.

Average daily sales

Average daily sales show how many units of a product are sold per day on average. This is the main parameter for demand forecasting.

How to choose the period for calculation:

stable product — you can take 60–90 days;

new items and fast-growing positions — 30 days or less to avoid smoothing out growth;

seasonal assortment — comparison with the same period last year, rather than recent months.

Days when the product was out of stock are excluded from the calculation. If periods of zero stock are included, average sales will be artificially underestimated, and the supply will be less than the actual need.

Current remaining stock

Only the stock available for sale at Wildberries warehouses is taken into account.

For an accurate calculation, it is important to:

check remaining stock for each item and warehouse separately;

rely on data from WB itself, not internal stock before the marketplace.

Goods in transit

Goods already shipped to Wildberries are subtracted from the new supply volume to avoid counting them twice.

Important to remember:

only actually shipped batches are included in the calculation;

planned but not yet shipped supplies are best not counted, as they may be delayed or change in volume.

If goods in transit are ignored, there is a risk of overestimating the supply and ending up with excess stock in the warehouse.

Production or procurement lead time

Production or procurement lead time is the full cycle from placing an order with a supplier to the batch being ready for shipment to Wildberries.

This includes:

order and specification approval;

actual production or procurement;

packaging;

labeling;

document preparation and readiness for shipment.

The longer this cycle, the more days of stock need to be planned to avoid stockouts.

Delivery and acceptance time

Delivery and acceptance time includes not only the journey to the WB warehouse but also unloading time, queuing, and actual acceptance.

It is important to set correct delivery times because:

the product does not start selling the moment the truck arrives;

actual times may differ from theoretical ones, especially during peak periods.

It is better to rely on actual data from past supplies: how long it takes on average from departure to the product appearing for sale.

Safety stock

Safety stock is a reserve for demand spikes or delays at any stage (production, logistics, acceptance). It is added to the forecasted demand to reduce the risk of shortages.

How to set the reserve size:

in units (e.g., +100 units);

in days of sales (e.g., +5 days of demand);

as a percentage of the forecasted volume (e.g., +10%).

Guidelines:

for stable products, the reserve is often 5–10%;

for seasonal and actively promoted items, the percentage is usually higher.

Formula for calculating supply to Wildberries

Supply volume = Average daily sales × Planning period + Safety stock – Current remaining stock – Goods in transit

Here, the "planning period" includes not only the days for which stock is needed but also the entire time until the new batch appears for sale:

Planning period = Production or procurement lead time + Delivery and acceptance time + Target stock period

Target stock period is the number of days the new supply should last after the product arrives at Wildberries warehouses.

Example of calculating supply to Wildberries: step by step

For clarity, let's break down a real example: how to get the recommended supply volume in units.

Initial data:

average daily sales — 15 units per day;

production — 7 days;

delivery and acceptance — 6 days;

target stock after arrival — 30 days;

current remaining stock at WB — 220 units;

goods in transit — 60 units;

safety stock — 65 units.

Step 1. Calculate the planning period

The planning period includes all stages before the product arrives and the target stock after arrival:

7 days (production) + 6 days (delivery and acceptance) + 30 days (target stock) = 43 days.

Step 2. Calculate the expected demand

Demand forecast for the planning period:

15 units per day × 43 days = 645 units.

Step 3. Add safety stock

Increase the volume considering the reserve:

645 + 65 = 710 units.

Step 4. Subtract remaining stock and goods in transit

Existing and incoming stock covers part of the need:

710 – 220 (remaining stock) – 60 (in transit) = 430 units.

Result: it is recommended to send the next batch with a volume of 430 units.

This figure should then be adjusted for seasonality, ad campaigns, participation in promotions, and distribution of goods across warehouses.

How to know when to make a supply to Wildberries

The start time of a supply is determined by how many days the current stock will last, and this is compared to the total production, delivery, and acceptance time.

Formula:

Days of stock = Current remaining stock / Average daily sales

Example:

current remaining stock — 300 units;

average daily sales — 15 units per day.

Calculation: 300 / 15 = 20 days of stock.

If production, delivery, and acceptance together take 16 days, then there are only 4 "extra" days of stock left. In such a situation, delaying the order is already risky.

The key principle: start the next supply before the replenishment time becomes longer than the remaining stock in days.

How to choose a Wildberries warehouse for supply

It's not enough to calculate the total quantity of goods — they need to be properly distributed across WB warehouses. The choice of warehouse affects delivery speed, the share of local orders, and final logistics costs.

The main principle: place goods closer to the main demand regions, not just where acceptance is cheaper.

When choosing a warehouse, consider:

sales geography by region;

current remaining stock at each warehouse;

sales speed at each warehouse;

acceptance cost;

logistics and warehouse tariffs;

availability of free time slots and supply dates;

localization index.

Wildberries shows sales by region and provides localization information. This helps understand where the product is bought most often.

A dangerous mistake is to send the entire batch to one warehouse just for cheap or free acceptance. If buyers are in other regions, savings on supply can easily turn into increased logistics costs and longer delivery times.

What factors affect supply volume

Supply volume cannot be calculated once based on "average sales" and never revised. The need is affected by seasonality, promotions, advertising, price, and demand dynamics.

Seasonality

For seasonal items (winter clothing, school supplies, garden assortment, etc.), demand varies greatly by month. Simply averaging sales over recent months is not enough.

What to consider:

when the season starts;

how long production and logistics will take to avoid being late with the supply;

how high the demand peak is during the season.

For such products, stock is increased in advance, based on last year's sales and planned promotions.

Wildberries promotions

Major promotions on WB usually accelerate sales. If you calculate the supply as if there were no promotion, the product may run out right during the promotion.

How to correctly calculate supply for a Wildberries promotion:

estimate in advance how many times orders may increase during the promotion;

increase the sales speed coefficient for the preparation and execution period of the promo;

recalculate the supply volume for the expected growth.

Advertising

An increase in advertising traffic almost always leads to an increase in orders. Therefore, when changing the advertising budget or launching new campaigns, the supply calculation needs to be updated.

Price change

After a price change, past average sales may no longer be relevant:

a price reduction usually increases demand;

a price increase may slow down sales.

After a significant price change, the period for calculating average sales should be updated, and you should not rely on a long history before the change.

Returns and redemption rate

Calculating supply based only on orders or only on redemptions are two different approaches.

Features of calculating supply considering returns and redemptions:

redemptions reflect real, paid demand;

orders help to see growing interest faster, but some are not redeemed.

If a product has a high return rate, calculating based on orders without considering redemptions will give an inflated need. For stable items, redemptions are more often used, while for products with rapidly growing demand, orders are sometimes taken and adjusted for the redemption rate.

Why overly large supplies are dangerous

Excessive supply to Wildberries leads to frozen capital in goods and increased storage costs. A large stock does not protect the business if demand falls or changes.

Main consequences:

storage costs increase;

capital turnover worsens;

the risk of dead stock increases;

goods have to be sold at a discount;

there is not enough working capital to purchase more in-demand categories.

Storage tariffs at WB depend on the volume of goods and the coefficient of the specific warehouse. Therefore, when calculating supplies, it is important to consider not only forecasted sales but also the cost of holding inventory.

How to automate supply calculation in Torgstat

With dozens and hundreds of items, manually calculating supplies for each product becomes time-consuming and inaccurate: while the table is being updated, stock and sales are already changing. In this case, it is more convenient to automate the calculation.

The Torgstat service has a "Supply Calculation" tool for Wildberries. It helps determine the recommended volume of the next supply for each item.

In the settings, you can set:

turnover period;

calculation base: all orders or only redeemed goods;

sales speed coefficient;

planned sales period;

number of units per box;

production and logistics lead time;

estimated supply date.

As a result, the seller forms the supply faster and reduces the risk of both shortages and excess stock.

Frequently asked questions

How often should the supply volume be recalculated?

For stable products, it is enough to review the calculation about once a week. For fast-growing, seasonal, and promoted items, the frequency should be increased.

Do I need to consider goods in transit when calculating supply?

Yes. Everything that has already been shipped to Wildberries and is actually in delivery or acceptance is subtracted from the new supply volume.

Do not include only planned but not yet shipped batches in the calculation — they may be delayed or change in quantity.

How to calculate supply for a new product with no sales history?

For a new item, you can rely on sales of similar products, category demand, and results from a test batch. It is better to make the first supply small, and after actual orders appear, recalculate the volume.

How to account for days when the product was out of stock?

Such days are best excluded from the calculation of average sales. Otherwise, the indicator will be underestimated, and the recommended supply will be insufficient.

Can I send the entire supply to one warehouse?

You can, but it is not always profitable. If orders come from different regions, sending the supply to one warehouse can increase delivery times, logistics costs, and reduce product localization.