DSO Calculator

Calculate how many days, on average, it takes to collect your accounts receivable.

Outstanding customer receivables at the end of the period.

Sales made on credit during the same period.

Target DSO

What is Days Sales Outstanding?

Days Sales Outstanding (DSO) measures accounts receivable relative to credit sales. It expresses the receivable balance as a number of days of sales.

Businesses use DSO to monitor collections and how much revenue remains tied up in accounts receivable. It is an aggregate figure, not the exact age of individual invoices.

DSO formula

DSO = (Accounts Receivable ÷ Credit Sales) × Number of Days

Accounts receivable: $250,000. Credit sales: $1,000,000. Period: 90 days.

($250,000 ÷ $1,000,000) × 90 = 22.5

DSO = 22.5 days

How to calculate DSO

  1. Find accounts receivable at the end of the period.
  2. Find credit sales for the same period.
  3. Divide accounts receivable by credit sales.
  4. Multiply the result by the number of days in the period.

Should DSO use revenue or credit sales?

The standard DSO formula uses credit sales because cash sales do not create accounts receivable.

If your accounting data does not separate credit sales from total sales, total sales may sometimes be used as an approximation, but the result should be interpreted accordingly.

Monthly, quarterly, and annual DSO

DSO can be calculated over different periods. Use the same period when you compare results over time.

  • Monthly: DSO = (AR ÷ monthly credit sales) × 30
  • Quarterly: DSO = (AR ÷ quarterly credit sales) × 90
  • Annual: DSO = (AR ÷ annual credit sales) × 365

What does a higher or lower DSO mean?

Higher DSO

A higher DSO means accounts receivable are larger relative to credit sales. It can indicate slower collections, longer payment terms, changes in customer mix, or other factors.

Lower DSO

A lower DSO means accounts receivable are smaller relative to credit sales. It can reflect faster collections, shorter payment terms, more cash sales, or other differences in the business.

DSO vs. payment terms

DSO and invoice payment terms measure different things. Net 30 tells a customer when an invoice is due. DSO measures accounts receivable relative to sales across the business.

A company with Net 30 terms and a DSO of 42 days has a receivable balance equal to approximately 42 days of credit sales. Use the Invoice Due Date Calculator to turn payment terms into a due date.

DSO vs. average collection period

DSO and average collection period are often used the same way: both describe how quickly receivables convert to cash relative to sales. The formula on this page is the common calculation for both.

DSO vs. AR aging

DSO is a single aggregate metric. An accounts receivable aging report groups individual receivables based on how long they have been outstanding.

Frequently asked questions

What is the formula for DSO?
DSO = (Accounts Receivable ÷ Credit Sales) × Number of Days. For $250,000 in receivables and $1,000,000 in credit sales over 90 days, DSO is 22.5 days.
What does DSO mean?
Days Sales Outstanding expresses accounts receivable as a number of days of credit sales. It is an aggregate metric for the receivable balance, not the exact collection time of any one invoice.
What is a good DSO?
There is no universal good DSO. Compare it with your payment terms, customer mix, and your own history. DSO varies by industry and billing practices, so a single threshold is not useful.
Should DSO use total sales or credit sales?
Credit sales are preferred because cash sales do not create accounts receivable. If your records do not separate credit sales, total sales can be used as an approximation, but read the result with that in mind.
Should I calculate DSO monthly or annually?
Either can be useful if you use the same period when comparing results. Shorter periods respond more quickly to changes and can also be more affected by seasonality.
Is DSO the same as invoice payment terms?
No. Net 30 tells a customer when an invoice is due. DSO measures accounts receivable relative to credit sales across the business.

Put the next invoice together in the Invoice Generator. For more on this metric, see Days Sales Outstanding and Accounts Receivable. Set due dates with the Invoice Due Date Calculator or Invoice Payment Terms. If an invoice is overdue, use the Late Payment Fee Calculator or browse All Calculators.