About this tool
Days Sales Outstanding (DSO) Calculator is a free, in-browser tool that measures how long, on average, it takes to collect payment after a credit sale. Enter accounts receivable, total credit sales for the period and the number of days in that period, and DSO is computed instantly on your device with nothing uploaded.
DSO = (accounts receivable ÷ credit sales) × days in period. With 50,000 in receivables against 500,000 of annual credit sales, DSO is 36.5 days. Optionally add inventory, accounts payable and COGS to also compute Days Inventory Outstanding, DIO = (inventory ÷ COGS) × days, Days Payable Outstanding, DPO = (accounts payable ÷ COGS) × days, and the cash conversion cycle = DSO + DIO − DPO — how many days cash is tied up between paying suppliers and collecting from customers.
Use it to monitor collections: a rising DSO signals slower-paying customers and tightening cash flow. A shorter cash conversion cycle frees up working capital, so many businesses work to cut DSO and DIO while extending DPO.