These calculators cover the recurring inventory math teams end up doing in a spreadsheet: when to reorder, how much buffer stock to hold, which SKUs deserve the tightest control, and what a bill of materials actually costs to build.
Each one shows the underlying formula, not just a result, so you can adapt it to your own numbers or sanity-check what another tool gave you.
If a calculator here answers "what should this number be," the matching glossary entry explains the concept behind it in more depth start with the term, then come back to run your own numbers.
Calculators
- Read guide →
Par level calculator
Calculate the minimum on-hand quantity for a SKU from average daily usage, lead time, and a safety buffer.
- Read guide →
Cycle count sample size calculator
Work out how many SKUs to count each day to hit your target count frequency across the whole catalog.
- Read guide →
Production yield calculator
Calculate first-pass yield and scrap rate for a production run from units started, good units, and rework.
- Read guide →
Inventory valuation calculator
Compare ending inventory value under weighted-average and FIFO costing from a beginning balance and one purchase.
- Read guide →
Reorder point & EOQ calculator
Enter average and peak usage plus supplier lead time to get a reorder point, safety stock buffer, and economic order quantity.
- Read guide →
Safety stock calculator
Size the buffer stock you need to absorb demand spikes and late deliveries without overstocking every SKU by the same amount.
- Read guide →
ABC analysis tool
Paste your SKU list and usage values to split inventory into A/B/C tiers by value contribution.
- Read guide →
Inventory turnover calculator
Turn cost of goods sold and average inventory value into a turnover ratio and days-to-sell figure.
- Read guide →
Average inventory calculator
Calculate average inventory from beginning and ending balances, or smooth it across several monthly values.
- Read guide →
Carrying cost calculator
Estimate what it actually costs to hold a unit in stock for a year capital, storage, insurance, and shrinkage combined.
- Read guide →
BOM cost calculator
Roll up component costs and a scrap allowance into a finished-good material cost for a multi-level bill of materials.
- Read guide →
EOQ calculator
Find the order size that minimizes combined ordering and carrying cost for one SKU.
- Read guide →
GMROI calculator
See how much gross profit a dollar tied up in inventory is actually generating.
- Read guide →
Days sales of inventory (DSI) calculator
Find how many days, on average, it takes to sell through your inventory.
- Read guide →
Landed cost calculator
Find the true per-unit cost of a purchased item once freight, duties, and fees are added.
- Read guide →
Inventory shrinkage calculator
Compare recorded stock value to a physical count to find your shrinkage rate.
- Read guide →
Stockout cost calculator
Put a rough dollar figure on a stockout, to weigh against the cost of more safety stock.
- Read guide →
Barcode generator
Generate a scannable Code 128, EAN-13, UPC-A, or Code 39 barcode and download it as a PNG.
- Read guide →
QR code generator
Generate a QR code for a SKU, product URL, or asset ID and download it as a PNG.
- Read guide →
Equipment utilization calculator
Work out what percentage of available time a piece of equipment actually spent in use.
- Read guide →
MTBF calculator
Calculate mean time between failures from operating hours and failure count, to set maintenance intervals from real data.
- Read guide →
Stock cover calculator
Days or weeks your current stock will last at the current demand rate.
- Read guide →
Inventory-to-sales ratio calculator
Average inventory value divided by net sales for the same period.
- Read guide →
Dead stock cost calculator
Holding cost of slow-moving and obsolete inventory.
- Read guide →
CBM calculator
Cubic meters and volumetric weight from carton dimensions.
- Read guide →
Lead time calculator
Add order processing, supplier production, transit and receiving days into one total lead time.
- Read guide →
Pallet calculator
Estimate cartons per pallet and pallets needed from carton size, pallet size and load height.
- Read guide →
Warehouse space utilization calculator
Occupied storage positions as a share of total positions.
- Read guide →
Order fulfillment cost calculator
Labor, packaging, overhead and postage divided by orders to get cost per order.
- Read guide →
3PL storage fee calculator
Pallet and bin storage plus receiving, pick-and-pack and per-unit fees for one client's monthly invoice.
- Read guide →
Perfect order rate calculator
Multiply on-time, in-full, damage-free and accurate-document rates.
- Read guide →
Picking productivity calculator
Lines and units picked per labor hour.
Trusted by small businesses
What our customers say
“Super Kind! Quick replies from their support and very easy fixes, changed the dashboard a bit and customized it. Also gave me 450 items extra on the free plan just for me. Highly recommend and again great service!”
“Best customer service! Stockflow's customer support is fast and extremely helpful. They assisted me with customization of the software to improve my experience as a user.”