Calculate Days Inventory Outstanding, Days Sales Outstanding, and Days Payable Outstanding — and combine them into the Cash Conversion Cycle to measure working capital efficiency.
The Cash Conversion Cycle (CCC) measures how many days a company's cash is tied up
in operations — from paying for inventory or inputs to collecting revenue from customers.
The CCC formula
CCC = DIO + DSO − DPO
Where:
- DIO (Days Inventory Outstanding) = Average Inventory ÷ COGS × 365
- DSO (Days Sales Outstanding) = Average AR ÷ Revenue × 365
- DPO (Days Payable Outstanding) = Average AP ÷ COGS × 365
Example calculation
A business with:
- Average inventory: $500k
- Annual COGS: $3M
- Average AR: $400k
- Annual revenue: $5M
- Average AP: $200k
DIO = $500k ÷ $3M × 365 = 60.8 days
DSO = $400k ÷ $5M × 365 = 29.2 days
DPO = $200k ÷ $3M × 365 = 24.3 days
CCC = 60.8 + 29.2 − 24.3 = 65.7 days
The company has $65.7 days of cash tied up in working capital on average.
Negative CCC: the holy grail
Some businesses — particularly SaaS (customers pay upfront) and retail giants
(sell before paying suppliers) — achieve negative CCC. That means they collect
cash before they need to pay their suppliers.
Amazon famously operated with a negative CCC for years, essentially using
supplier credit as free working capital to fund growth.
CCC for SaaS businesses
Pure SaaS businesses typically have:
- DIO = 0 (no physical inventory)
- DSO = depends on payment terms (0 for monthly subscriptions, 30–60 for invoiced enterprise)
- DPO = depends on supplier payment terms (usually 30–60 days)
SaaS with monthly card billing and standard payables often has CCC near 0 or negative.
How to improve CCC
Reduce DIO: Faster inventory turns through better demand forecasting, reduced
safety stock, or just-in-time procurement.
Reduce DSO: Offer early payment discounts, automate collections, shorten
payment terms for new customers, implement automatic billing.
Increase DPO: Negotiate longer payment terms with suppliers (60–90 days vs
30 days). Large companies do this systematically.
Frequently asked questions
What does this calculator do?
Calculate Days Inventory Outstanding, Days Sales Outstanding, Days Payable
Outstanding, and combine them into the Cash Conversion Cycle.
What Is the Cash Conversion Cycle? A Working Capital Guide
The Cash Conversion Cycle (CCC) measures how long cash is tied up in operations. This guide explains DIO, DSO, and DPO — and how to use CCC to improve working capital efficiency.
The Cash Conversion Cycle (CCC) answers: how many days does it take from when
you spend cash on inputs to when you collect cash from customers?
CCC = Days Inventory Outstanding + Days Sales Outstanding - Days Payable Outstanding
A lower CCC means you turn operations into cash faster — freeing working capital
for growth without additional financing.
Breaking down the three components
DIO — Days Inventory Outstanding
How long inventory sits before being sold.
DIO = Average Inventory ÷ COGS × 365
At $500k average inventory and $3M annual COGS: DIO = 60.8 days.
Lower DIO = faster inventory turns = less cash tied up in stock.
DSO — Days Sales Outstanding
How long it takes to collect payment after a sale.
DSO = Average Accounts Receivable ÷ Revenue × 365
At $400k average AR and $5M revenue: DSO = 29.2 days.
High DSO indicates slow collections — either loose payment terms, slow invoicing,
or customers paying late.
DPO — Days Payable Outstanding
How long you take to pay suppliers.
DPO = Average Accounts Payable ÷ COGS × 365
At $200k average AP and $3M COGS: DPO = 24.3 days.
Higher DPO = you hold cash longer before paying = better for working capital.
Using CCC for business planning
High CCC businesses need more working capital (and often credit lines) to fund
growth. Low or negative CCC businesses can grow with minimal external financing.
If you're planning to double revenue, your working capital requirement scales
roughly proportionally with CCC — a 65-day CCC at 2× revenue means 2× the
cash tied up in operations.
How to Reduce Days Sales Outstanding (DSO) in B2B SaaS
High DSO ties up cash in uncollected invoices. This guide covers the most effective tactics for reducing DSO in B2B SaaS businesses — from payment terms to automated collections.
Days Sales Outstanding (DSO) is one of the most actionable components of the
Cash Conversion Cycle. Every day you reduce DSO frees up working capital.
At $5M ARR with 30-day DSO: $5M ÷ 365 × 30 = $411k tied up in AR.
Reduce DSO to 15 days: AR drops to $205k — $206k freed up immediately.
Tactic 1: Require upfront annual payment with a discount
The most powerful DSO lever in SaaS: offer 15–20% annual discount for prepayment.
Annual payers have DSO = 0 the moment they pay. Monthly payers on invoices have DSO = 30–60.
Moving 30% of customers from monthly to annual can cut DSO in half.
Tactic 2: Switch from invoice to automatic card billing
Monthly invoices create DSO. Automatic card charges have DSO ≈ 0 (aside from
settlement processing, which is 1–2 days).
For self-serve and SMB customers: require automatic billing. For enterprise:
keep invoicing but tighten terms.
Tactic 3: Automate collections sequences
Set up automatic reminder emails:
- 3 days before due: "Invoice due soon"
- Day 0 (due date): "Invoice due today"
- Day 7: "Invoice overdue"
- Day 14: "Second notice — payment required to avoid service interruption"
Automated sequences reduce DSO by 30–50% vs. manual follow-up.
Tactic 4: Shorten standard payment terms
Net 60 → Net 30 → Net 15 → Due on receipt. Each reduction directly cuts maximum DSO.
Large customers may push back. Hold firm on standard terms for smaller accounts.
Tactic 5: Require ACH/wire for enterprise
Credit card chargeback risk incentivizes some enterprises to delay. ACH payments
are faster and have no chargeback risk. Offer ACH as the default for enterprise invoices.
SaaS businesses have unique working capital dynamics. This guide explains how CCC applies to SaaS, why most SaaS companies have negative working capital, and how to optimize it.
Working capital is the difference between current assets and current liabilities.
Managing it well means having cash available when you need it without over-financing.
For SaaS businesses, working capital management is simpler than for product
businesses — but still important, especially at scale.
Why SaaS often has negative working capital
A SaaS business with annual billing and monthly payables has:
- DIO = 0 (no inventory — purely digital)
- DSO ≈ 0 (customers pay upfront or via auto-billing)
- DPO = 30–60 days (paying AWS, payroll, vendors 30–60 days after service)
CCC = 0 + 0 − 45 = −45 days
Negative CCC means the business is operating on supplier credit — collecting
revenue before it needs to pay suppliers. This is naturally cash-generative.
Contrast with a services business invoicing net 30 with 60-day supplier terms:
- DSO = 30 days, DPO = 60 days
- CCC = 30 − 60 = −30 days (still negative, but less so)
When SaaS working capital turns positive
Working capital can turn negative in SaaS when:
- Large enterprise deals are invoiced net 30–60 (high AR builds up)
- Hiring and expenses outpace cash collection velocity
- Deferred revenue from annual contracts isn't matched with cash reserves
A $10M ARR SaaS with 50% enterprise (net 45 payment terms):
- Enterprise AR: $5M ÷ 365 × 45 ≈ $616k outstanding at any time
- Non-trivial — and doubles at $20M ARR without process improvement
Optimizing SaaS working capital
Push for upfront annual billing across enterprise — reduces AR and improves DSO
Automate monthly billing for SMB/mid-market — eliminates AR entirely