DSO calculator
Days sales outstanding shows how long customers take to pay. Enter your receivables and credit sales for the period to get DSO, the average collection period and receivables turnover.
Calculation summary
Calculated liveCredit sales $120,000.00, receivables $30,000.00
DSO = receivables ÷ credit sales × days. Use credit sales only, not cash sales.
Instant breakdown
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Formula you can check
The formula and a worked example sit below the tool, so you can verify the result yourself.
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Create an invoiceHow to calculate DSO
DSO tells you how many days of sales are stuck in unpaid invoices. Divide your accounts receivable by your credit sales for the period and multiply by the days in that period.
Use the same period for all three numbers. A rising DSO is an early sign that customers are paying slower or that collections need attention.
Common questions
Clear answers on contract law, calculations and enforcement.
What is DSO?
Days sales outstanding is the average number of days it takes to collect payment after a credit sale. Lower is better.
How do you calculate DSO?
Divide accounts receivable by credit sales and multiply by the days in the period. 30,000 ÷ 120,000 × 90 = 22.5 days.
What is the average collection period?
It is the same measure as DSO, also called the average debtors collection period: receivables ÷ credit sales × days.
What is receivables turnover?
Credit sales divided by receivables. It shows how many times a period you collect your average balance. DSO is the days in the period divided by turnover.
What is a good DSO?
Compare it to your payment terms. A DSO close to your terms, such as 30 to 40 days on Net 30, is healthy. A DSO well above your terms means customers pay late.
How can I lower my DSO?
Send invoices promptly, state clear terms, send reminders before and after the due date and offer easy payment links.