Days Sales of Inventory Calculator
How many days your current stock will last.
Days sales of inventory
61 days
6.0 turns a year
How the Days Sales of Inventory Calculator works
DSI converts turnover into a unit people can actually plan with. Six turns a year is abstract; 61 days of stock on hand tells you immediately whether that is comfortable or alarming for your lead times.
Not financial advice. Marketplace fees change, and they vary by country, plan and seller status. Every rate here is an editable default, not a quoted price — check the platform's current fee schedule before you price a product against it. This is not tax or business advice.
Frequently asked questions
How is DSI calculated?
(Average inventory ÷ cost of goods sold) × 365. Equivalently, 365 ÷ inventory turnover. £40,000 of average stock against £240,000 of annual COGS is 61 days.
What is a good DSI?
Low enough that cash is not trapped, high enough that you do not stock out. It must comfortably exceed your supplier lead time — 30 days of stock with a 45-day lead time guarantees a gap.
How does DSI relate to the cash conversion cycle?
It is one of the three components, alongside days sales outstanding and days payable outstanding. Cash conversion cycle = DSI + DSO − DPO. Reducing DSI shortens the time your money is locked in stock.
Is DSI the same as days on hand?
Effectively yes, though days on hand is sometimes calculated on current rather than average inventory, and sometimes on units rather than cost. Check which basis a benchmark uses before comparing against it.